351C 4V Valve and valvetrain replacement

7173Mustangs.com

Help Support 7173Mustangs.com:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
The book I have is the one that has been recommended by several members by Tom Monroe.
Ok, xlnt, since I have actually written portions of service manuals when I ran the R and D department for a major vehicle mfg for several years, my guess is that he meant to say something like:

"The minimum depth of the front cam bearing is .003" . The maximum depth is .020" providing the oil galley is not exposed."

.......................................... This is the factory Ford manual which states what I posted.

frontcambearing.jpg~original


 
Last edited by a moderator:
I have actually written portions of service manuals when I ran the R and D department for a major vehicle mfg for several years
Really. Which ones and what years?

 
I don't get what the big deal is about asking to have the front bearing installed to spec. Clearly it's installed wrong. Is it going to be a problem maybe / maybe not, sure is a lot easier to fix now vs once the engine is in the car. Your the customer PAYING FOR A SERVICE. Why you should feel that your gonna piss off the guy doing work for something he did wrong is irrelevant. I mean if you have to feel like he's doing you a favor for a service your paying for than your dealing with the wrong guy. My take, Ask to have it corrected and if he cops a attitude well tuff s***. Ask him to stop work..pay for what he did pull the motor and go elsewhere. In today's economy there's PLENTY of competent motor builders machine shops who will bend over backwards be happy to have the work and service the customer properly.

 
I have been following this discussion carefully as I am at this point in a stock rebuild also. It is very obvious that there are several points of view on this subject especially concerning the depth that the first cam bearing is set at form the block surface. I happen to have a virgin block that has not been reworked at all. I measured the depth of that bearing to be .060" down and the oil hole is clearly visible. I have no doubt that this is from the factory, given the overall condition of this block and it's known history. There is only one other scenario and that is that the bearing actually shifted over time............, but this is highly unlikely. Just thought I'd throw that into the mix!! My block picture attached.

While I'm at it, I find it both confusing and disheartening that certain 'adults' continue to bicker about who's right and who's wrong on this forum. Like most of us, I have a relatively good level of intelligence and as such I'm reasonably able to figure out what information is valuable and what is not, or at least what I should further investigate. I for one, would greatly appreciate getting FACTS rather than childish bickering....... can we all get along and do that???

Nuff said, I have gained from this post, so thanks to all for that.

Geoff.

PS. Just for the heck of it, I just Googled 351C cam bearing location and there was "images of 351C cam bearings" Some are as original by the looks of it and some are modified. Point is most are at least 60 thou. in as is on my block.

 
Last edited by a moderator:
I have been following this discussion carefully as I am at this point in a stock rebuild also. It is very obvious that there are several points of view on this subject especially concerning the depth that the first cam bearing is set at form the block surface. I happen to have a virgin block that has not been reworked at all. I measured the depth of that bearing to be .060" down and the oil hole is clearly visible. I have no doubt that this is from the factory, given the overall condition of this block and it's known history. There is only one other scenario and that is that the bearing actually shifted over time............, but this is highly unlikely. Just thought I'd throw that into the mix!!
Since the factory spec is in fact .003" to .005", this simply proves that errors were made . Keep in mind that this process was done by hand often by workers whom might have had a few too many beverages the night before . These workers are human beings not robots, therefore they are fallible . Also, the quality control inspectors do not inspect the installation of every part . They occasionally come buy and check the parts, and because of this, some things like the bearing being installed deeper than the spec calls for can and does occur.

PS. Just for the heck of it, I just Googled 351C cam bearing location and there was "images of 351C cam bearings" Some are as original by the looks of it and some are modified. Point is most are at least 60 thou. in as is on my block.
Well the fact is that this is still much deeper than the factory spec and even deeper than the spec given by Tom Monroe in his book which is .015" deeper than the factory spec and it comes down to this, just because someone else did it wrong, even if it was done at the factory, it is no reason to copy their mistake.

We even have lemon laws and recalls of hundreds of thousands of vehicles now do to incorrectly designed parts etc, so this is further proof that just because it was done at the factory, it doesn't mean it was done correctly.

While I'm at it, I find it both confusing and disheartening that certain 'adults' continue to bicker about who's right and who's wrong on this forum. Like most of us, I have a relatively good level of intelligence and as such I'm reasonably able to figure out what information is valuable and what is not, or at least what I should further investigate. I for one, would greatly appreciate getting FACTS rather than childish bickering....... can we all get along and do that???

Nuff said, I have gained from this post, so thanks to all for that.
I couldn't agree more, and I am a fact based person which you can see from my posts and I feel compelled to correct inaccurate info when I know it is inaccurate or not completely accurate . I also try to separate my opinions from empirical facts which some people don't do, and imo, posting opinions in a way that they can be misconstrued as empirical facts is a disservice to everyone reading them if in fact they are wrong because some people whom are trying to learn because they aren't familiar with a particular subject might take them as Gospel and possibly even damage their engine because of what they read.

I will also add that I received a pm from a moderator regarding this very issue in which he applauded me for not replying to others taunting and attempts to discredit me by trying to get me to say where I worked or what service manuals I have contributed to etc, and in fact, if I did this, it might embarrass some of these people which is not my intent . None of these forums require proof of an engineering degree etc to join, and in my experience, there are many people whom are basically self taught whom have learned from years of hands on experience whose opinions are extremely valuable and helpful even though they don't have a degree or have their own shop etc . As far as I am concerned, I am quite happy if I post something that is incorrect or vague and someone else corrects, or clarifies it, because in my job, the truth/facts are all that matter, and I prefer to learn new things as opposed to not.

.

 
Last edited by a moderator:
Damn.....

I would fix it - not because it is not exactly to the correct factory specification but that the passages that go to the mains and the valve train are about 1/2 covered.

The other oil opening is on the leading and BEVELED edge of the cam journal in the block. Placing the cam bearing more forward - thus hanging over this BEVELED area - does not and can not close it off anymore than it already is. This opening must be and will always be uncovered just a bit.

This offending oil passage that is on this beveled edge is in the front of the bearing journal and sprays the back of the thrust plate This is on the opposite side and directs oil in the exact opposite direction of the distributor gear.

2a0jed2.jpg


In the above image the oiling passage we are discussing can be seen adjacent to the cam drive pin. How will oil coming out of this opening lubricate the distributor gear which is behind the first cam shaft journal and is inside the block?

If you drill a hole it the galley plug - it will also spray oil forward and out of the block not into the block. How will this do anything to lubricate the distributor drive gear that is inside of the block? It would obviously spray a stream of oil on the back of the upper timing gear.

If you look at a Cleveland block you will see what looks like a rough hole in the front of the lifter valley.

v2shnt.jpg


This is directly above the cam and distributor gear junction and allows oil to get to cam and distributor gears from the lifter valley. Very early 351C blocks did not have this opening and they had distributor gear failures.

Instead of creating an expensive new block casting they just knocked this already thin area open. It was probably the last official step at the foundry.

"Now take specialty tool x1000 (big hammer) and break out thin area between first 2 lifter bores"

Lastly - in the block where the oil pump shaft and the distributor shaft meet there is a oil galley hole.

20z9xzm.jpg


It can be seen just to the left top center of the hole in the above image.

This in theory should lubricate the distributor gear but in real life gravity causes more oil to come out the bottom than out of the top. Hence the need for specialty tool x1000 (big hammer).

I no longer own a business. I am not published. I am not helping someone in Australia. I have had more than one cam shaft failures on engines I have built.

And I get grumpy if I do not have my morning coffee.

Sorry if I am being vague.

OK Xlnt,

Paul of MO

 
Last edited by a moderator:
I have been following this discussion carefully as I am at this point in a stock rebuild also. It is very obvious that there are several points of view on this subject especially concerning the depth that the first cam bearing is set at form the block surface. I happen to have a virgin block that has not been reworked at all. I measured the depth of that bearing to be .060" down and the oil hole is clearly visible. I have no doubt that this is from the factory, given the overall condition of this block and it's known history. There is only one other scenario and that is that the bearing actually shifted over time............, but this is highly unlikely. Just thought I'd throw that into the mix!!
Since the factory spec is in fact .003" to .005", this simply proves that errors were made . Keep in mind that this process was done by hand often by workers whom might have had a few too many beverages the night before . These workers are human beings not robots, therefore they are fallible . Also, the quality control inspectors do not inspect the installation of every part . They occasionally come buy and check the parts, and because of this, some things like the bearing being installed deeper than the spec calls for can and does occur.

PS. Just for the heck of it, I just Googled 351C cam bearing location and there was "images of 351C cam bearings" Some are as original by the looks of it and some are modified. Point is most are at least 60 thou. in as is on my block.
Well the fact is that this is still much deeper than the factory spec and even deeper than the spec given by Tom Monroe in his book which is .015" deeper than the factory spec and it comes down to this, just because someone else did it wrong, even if it was done at the factory, it is no reason to copy their mistake.

We even have lemon laws and recalls of hundreds of thousands of vehicles now do to incorrectly designed parts etc, so this is further proof that just because it was done at the factory, it doesn't mean it was done correctly.

While I'm at it, I find it both confusing and disheartening that certain 'adults' continue to bicker about who's right and who's wrong on this forum. Like most of us, I have a relatively good level of intelligence and as such I'm reasonably able to figure out what information is valuable and what is not, or at least what I should further investigate. I for one, would greatly appreciate getting FACTS rather than childish bickering....... can we all get along and do that???

Nuff said, I have gained from this post, so thanks to all for that.
I couldn't agree more, and I am a fact based person which you can see from my posts and I feel compelled to correct inaccurate info when I know it is inaccurate or not completely accurate . I also try to separate my opinions from empirical facts which some people don't do, and imo, posting opinions in a way that they can be misconstrued as empirical facts is a disservice to everyone reading them if in fact they are wrong because some people whom are trying to learn because they aren't familiar with a particular subject might take them as Gospel and possibly even damage their engine because of what they read.

I will also add that I received a pm from a moderator regarding this very issue in which he applauded me for not replying to others taunting and attempts to discredit me by trying to get me to say where I worked or what service manuals I have contributed to etc, and in fact, if I did this, it might embarrass some of these people which is not my intent . None of these forums require proof of an engineering degree etc to join and in my experience, there are many people whom are basically self taught whom have learned from years of hands on experience whose opinions are extremely valuable and helpful . As far as I am concerned, I am quite happy if I post something that is incorrect or vague and someone else corrects, or clarifies it because in my job, the truth/facts are all that matter and I prefer to learn new things as opposed to not.

.
Barnett, Thanks for your input. I also worked in the Auto industry for 35+ years, you don't have to tell me about stuff not getting done to spec. Seen it all too. My engine build will be done to spec knowing now what it is. I don't have that depth spec, so this post has given me that information.

As for my other comment on some people bickering........... I didn't mention any names. However, as you comment, facts are facts, but some "facts" get distorted from time to time. These discrepancies can be presented in a courteous manner, that's all I'm saying. Nuff said.

Geoff.

 
If you drill a hole it the galley plug - it will also spray oil forward and out of the block not into the block. How will this do anything to lubricate the distributor drive gear that is inside of the block? It would obviously spray a stream of oil on the back of the upper timing gear.
xlnt question which I will gladly answer . There are two galley plugs as you know, so the hole in the one on the drivers side will spray oil directly on the back side of the distributor shaft which in turn will splatter on the gears as well as run down the shaft directly onto the top of the distributor gear where it will be flung in all directions, one of them being directly onto the interface of the gears.

Obviously the timing chain won't seize so the mod here is less important imo, however, it too is lubricated by splash instead of direct lube, and as I think we all know, in most, if not all cases, more oil is better than less, therefore, things do not get prematurely worn or damaged by getting too much lubrication but they sure won't last very long with too little.

I have also seen it recommended many times to use a hole that is .030" which imo is unnecessarily large which is why I posted the video of the .020" hole in the lifter bore gushing huge amounts of oil out with just the pressure from a hand pump . Also, obviously the bigger the hole, the more oil that comes out of it and since the smallish size hole I suggested will still spray a lot of oil, I prefer to be a bit conservative and only use the size that I think is sufficient to do the job instead of doing what I think is huge overkill.

..............................................
images


 
Last edited by a moderator:
OK - now that we have that out of the way (again), let's stay focused.

We all have a lot to bring to the table regarding various topics - nobody is the "end-all, be-all" for anything and/or everything... we all have our areas of expertise and strong points. All we can do is provide information about the things we know, share our experiences, collaborate with each other, and help those who ask get headed in the right direction by presenting options - whichever way that might be to best suit their needs.

In my observations, nobody I know or have witnessed here has ever provided or presented misinformation or attempted to mislead others when they've requested assistance. That speaks volumes of our members and our desire to help others achieve the best results in our endeavors.

Let's try to keep that in mind when we think about throwing the shade... no matter how subtle we think we might be, someone's always going to pick up on it and pull negative impressions. I am of the firm belief that we're all friends here, and can settle our differences rationally without lowering our standards.

:threadjacked:

 
Barnett, Thanks for your input. I also worked in the Auto industry for 35+ years, you don't have to tell me about stuff not getting done to spec. Seen it all too. My engine build will be done to spec knowing now what it is. I don't have that depth spec, so this post has given me that information.

As for my other comment on some people bickering........... I didn't mention any names. However, as you comment, facts are facts, but some "facts" get distorted from time to time. These discrepancies can be presented in a courteous manner, that's all I'm saying. Nuff said.

Geoff.
No problem, and for the record, imo, everyone whom is offering suggestions on this thread are very knowledgeable about engines, however, no one other than Smokey Yunick knows it all, and different people often know different things.

As far as working in the auto industry for that long, yes I'm sure you have seen more than your fair share of faux pas, but I still have faith, albeit possibly misguided , that most mfg's truly want to make a decent product even if they know they are making a budget priced one, but as the saying goes..."Sh_t happens.", lol.

 
Last edited by a moderator:
Okay, I did just find in my original 1971 Car Shop Manual, the reference to the #1 bearing specified depth and Barnett in right, it IS .003" - .005". SO, is it possible that the bearing actually moves over time, making it look like the depth is far greater?? Unlikely I agree, but..............., or is it just bad workmanship from the factory. I guess we'll never know for sure, so better do it to spec and leave it at that.

 
So you suggest that someone drills a hole in the most recessed galley plug back in the block?

Every oil modification for a 351C is to restrict oil flow to the valve train and/or to send more PSI to rods and mains. This plug is at the very beginning of the oil system and to intentionally cause a leak at this point makes no sense.

This plug back in the block is not even directly in line with the distributor shaft - the small high pressure jet of oil exiting this plug would probably just sail on past it and splatter on the back of the timing gear. I guess if you built a jig to hold the plug at an angle when causing the leak - then carefully indexed it when installing the plug in the block there could be some benefit for distributor gear but at the risk of the rest of the engine.

You have said that dist gear failure is rare now days. It was rare in my day, actually non existent. So are we fixing something that is not broken?

I never did the galley plug leak modification even on 10,000 rpm race engines. Never researched it and never saw any other professional builder do it. Thanks for educating me on it. I always assumed it was done to the galley plug that was at the very end of the oil line directly behind the timing gear - now I am even more certain that it is a stupid idea.

If this was a viable fix for distributor gear failure issues then I bet Ford would have simply supplied drilled galley plugs instead of knocking the hole in the valley.

(That is unless they were to drunk to install them correctly.)

Have you actually ever, one single time, installed a drilled galley plug in a Cleveland?

- Paul of MO

I do agree this is a jacked thread - just do not want someone to do this modification an loose an engine because of it - So I am done.

 
Last edited by a moderator:
One can actually drill the hole on the distributor side plug at a slight angle, however, even if they don't it will still hit the shaft.

As I previously mentioned, which you obviously didn't see, the stock factory engines never had a problem with the distributor gear, but no one is using stock factory parts, and as I also mentioned, there have been around a bazillion gear failures in different engines . I did not personally inspect all bazillion of them so I can't say for certain why all of them occurred, however, I do know for a fact why some of them occurred.

Also as I also previously mentioned, the size of the holes I suggested is insignificant in the big scheme of things because if you calculate the area/size they are and compare that size to the one between the lifter and lifter bore, you will find that each hole it is probably equivalent to clearance between just 2 lifters and their bores, and you actually implied that the amount of oil that comes from this area is insufficient to properly lubricate the cam during break in, which is exactly why you suggested breaking them in at 3000 rpm which in fact is 500 rpm higher than any cam mfg recommends.

Also, it is a fact that an open oil galley in the front cam journal that is maybe the equivalent to around 1/4" in size, is a far greater concern than two tiny holes in lifter galley plugs whose combined size may be around 6 or more times smaller.

If this was a stock engine using stock cam and distributor gear and timing chain, I would see no need for this mod, but this is not the case.

Also, as I have mentioned, he may have absolutely no problem if he doesn't do this mod, however, since it can not possibly do any harm, and can only possibly help, I see no reason not to.

Now, imo this subject has been beaten to death, and I for one see no point in beating it any longer and I can't think of any more to add regarding it that will be significant, therefore, unless I do, I won't . My guess is that Mystic Fish now has enough information regarding it to make an educated, informed decision regarding it.

As far as burnishing the gear on the cam before installation to help reduce the chance of premature failure goes, Chase Knight from Crane cams actually recommended that it be done on ANY cam prior to installation, so whom am I to argue with one of the biggest cam mfg's in the world, especially when I have seen benefits from doing this in some cases.

.

 
Last edited by a moderator:
I stand corrected:

http://www.teampanteraracing.com/gallery2/main.php?g2_itemId=4450

This a full road race Pantera but they did drill this plug out. (and my logic was correct they had to drill it at an angle)

The rest of their oiling system is heavily modified and I am sure it compensates for the PSI loss.

I still would not do this on a street spec'd engine.

- Paul of MO

 
OK - now that we have that out of the way (again), let's stay focused.

We all have a lot to bring to the table regarding various topics - nobody is the "end-all, be-all" for anything and/or everything... we all have our areas of expertise and strong points. All we can do is provide information about the things we know, share our experiences, collaborate with each other, and help those who ask get headed in the right direction by presenting options - whichever way that might be to best suit their needs.

In my observations, nobody I know or have witnessed here has ever provided or presented misinformation or attempted to mislead others when they've requested assistance. That speaks volumes of our members and our desire to help others achieve the best results in our endeavors.

Let's try to keep that in mind when we think about throwing the shade... no matter how subtle we think we might be, someone's always going to pick up on it and pull negative impressions. I am of the firm belief that we're all friends here, and can settle our differences rationally without lowering our standards.

:threadjacked:
Eric, well said!!



Barnett, Thanks for your input. I also worked in the Auto industry for 35+ years, you don't have to tell me about stuff not getting done to spec. Seen it all too. My engine build will be done to spec knowing now what it is. I don't have that depth spec, so this post has given me that information.

As for my other comment on some people bickering........... I didn't mention any names. However, as you comment, facts are facts, but some "facts" get distorted from time to time. These discrepancies can be presented in a courteous manner, that's all I'm saying. Nuff said.

Geoff.
No problem, and for the record, imo, everyone whom is offering suggestions on this thread are very knowledgeable about engines, however, no one other than Smokey Yunick knows it all, and different people often know different things.

As far as working in the auto industry for that long, yes I'm sure you have seen more than your fair share of faux pas, but I still have faith, albeit possibly misguided , that most mfg's truly want to make a decent product even if they know they are making a budget priced one, but as the saying goes..."Sh_t happens.", lol.
You're quite correct in your above comment. Thanks for your help.

Geoff.

 
Last edited by a moderator:
.

Ok, I decided to calculate the actual area of the .016" hole which is the size I suggested for the lifter galley plug and compare it to the area between the lifter and the lifter bore using .001" as the "guestimated" clearance.

Using .001" as the clearance, the area of the clearance between just one lifter and lifter bore is .00112 sq inches MORE than the area of a .016" hole . This is a whopping 5.56 times larger or 459% larger . With these figures, one can decide for themselves how significant the additional "leak" a .016" hole in each lifter galley will be.

lifter bore area ..................................................................... .60270

lifter area ............................................................................ .60132

area of clearance .................................................................. .00138

area of .016" hole in lifter plug ................................................ .00020

difference in area between lifter clearance and .016" hole ........... .00112

 
Last edited by a moderator:
I'm a dumbshit when it comes to engines.

There's a lot of discussion of what's right and what's wrong, but everyone is making the same assumption: the printed Ford spec is correct.

What if it was a misprint? This is not unknown in Ford Shop Manuals.

 
I'm a dumbshit when it comes to engines.

There's a lot of discussion of what's right and what's wrong, but everyone is making the same assumption: the printed Ford spec is correct.

What if it was a misprint? This is not unknown in Ford Shop Manuals.
Yes, errors in manuals do occur and I have seen some, however if you question the cam bearing spec, you must question everything else in the factory manual which imo is illogical, because if one does that, they might as well not use it at all, and if they don't use it, imo it is even more illogical to trust a third party manual like a Haynes or a Clymer etc, so at that point they might as well just make up their own specs and hope for the best . This being said, experienced mechanics can tell if a spec is wrong simply based on their past experience.

The simple fact that remains is that the more of the oil hole is exposed, the more oil that will gush from it up to the limits allowed by the cam gear to retainer plate clearance which is a lot.

One problem is that not all manuals, or all parts of some manuals are written by engineers, and those are the ones I have seen the most errors in.

 
Last edited by a moderator:
Good evening everyone,

Since my original question regarding stock valve springs was answered and not thinking that 40 year old springs should be replaced anyway, I have realized that yes, we need to replace all of the springs.

My later follow up question regarding stock spring rates got a little lost somewhere along the way, but it was also determined that the stock rates are much too low for any camshaft that would be installed. After studying the book by Tom Monroe a little I found what I was looking for. The factory spec spring rates for both open and closed valves.

image.jpg

The specs for stock 4V valve springs are finally discovered.

 
Back
Top