351 engine tear down

[Manu Mach1]

I'm originally an auto mechanic but I've hardly ever done it professionally, just for myself, for my own enjoyment, and for family and friends when needed. Everything I do on my Mustang I learned here, we have a lot of similarities, then come some differences between the coupes, convertibles and Sportroof and Mach1.
We have a lot of litterature that helps us understand and do repairs, maintenance.
On my side I share my knowledge and if I can help I will.
We are not born with an infinite science, we learn every day.

 

[Manu Mach1]

In the FELPRO gasket kit, there are these valve stem seals. There are two bags with different gaskets, one for the intakes (16 pieces) and one for the exhausts (8 pieces). I wonder if these gaskets are very effective because they do not completely close the oil passage. What do you think?

 

[Don C]

They are not very effective. The best are the positive Viton seals. However, they require machining the top of the valve guide. Have them machined at the same time you have new valve guides installed.

 

[Manu Mach1]

I have already had new valve guides fitted. I am not going to have the cylinder heads modified yet. In this case, can I install the same 16 valve stem seals and not use the ones for the exhaust? As the intake ones are longer, they should be more efficient?

 

[Don C]

I don't think it'll make any difference on the exhaust, they are just umbrellas to keep the oil from running down the stems. The exhaust pushes gases out of the exhaust valve guides, and doesn't suck them in like around the intake guides.

Edit: Using the longer seals on the exhaust will provide more chunks to break off and clog the oil pickup when they begin disintegrating. The exhaust seals are the first to fail, due to the heat.

 

[Manu Mach1]

That is the reason why the exaust ones have this design, I didn't know, thanks. 

 

[Manu Mach1]

As it's my first engine completely disassembled, well, I have to do it the other way around without doing anything stupid.
So I'm going slowly, I've got some literature, I'm gleaning information right and left, and come what may.
I will be a long reassembly, but I prefere that at the end the engine starts.

 

[vintageman]

Take your time, lots of pictures and measurements when you do your rebuild. I picked up a timing wheel and verified all of the settings received at least 2 or 3 times each. I also made sure I picked up some plastigage for bearing checks. During this time, I found that a couple of my connecting rods were installed backwards by the company that heated them up and installed them. Take your time, do some research. I also followed videos by Peter Anderson on YouTube, he has an entire video series on rebuilding the 351C and is very knowledgeable on it. Good luck, attention to detail when installing the piston rings, rods, and timing is a must. Good luck and I can't wait to hear it running.

Tom

 

[Manu Mach1]

Oh yes, Peter Anderson, I saw videos on Youtube from him, I know what you mean, I am subscribed to his channel.
My next step is to plastigage the crankshft. I will post the steps.

 

[71ProjectJunk]

I have not built an engine in decades, but double and triple check everything. Plastigauge is your friend as vintageman said. Check all clearances, if anything seems a little bit off just stop and figure it out. Machine shops do make mistakes. Put the crank in and rotate it by hand, make sure it moves smoothly, same with the cam, there should be no binding anywhere. I have seen issues where the cam bearings are not installed correctly by machine shops. When the short block is together rotate everything by hand make sure that everything moves smoothly, then do the same when you have the long block together, if something does not feel right stop and figure it out. Lots of assembly lube. Make sure everything is not only torqued to spec, but that you follow the torqueing process by the book. Double check that the pistons are in the right orientation and that the rods are also in the correct orientation, same with your bearings. If you have a bigger cam than stock check your piston to valve clearance, make sure that you have the correct clearance. If you changed valve springs make sure that they are installed at the correct installed height and that you have plenty of clearance between the retainers and the head. Check thrust bearing crank clearance, rod to crank clearances. Most important is to take your time, slow and steady and again check all clearances. Make sure the rear main seal is installed in the correct orientation and that it is offset a bit. If the machine shop did their job correctly, putting and engine together is not hard, the issue is if they made a mistake, or some part if out of spec, you need to be able to find it in the process of putting it together, that is the difficult part... After it is together make sure that it will start fast so you can do your cam break in, after all this work, you do not want to wipe out the cam because the damn thing will not start, especially with todays crappy lifters, LOL

 

[tony-muscle]

All the above comments are so true in relation to double and triple checking, take your time and use references. When it comes to valve train things can get very tricky and if you are upgrading there are little things that the old Cleveland book is not going to tell you. This is very true when upgrading rockers, upgrading lifters, or modifying spring installed height, or milling heads. If so, you need to make sure you measure the proper push rod length to keep the valvetrain geometry. Little things like what I learned this week, and I had missed in the past, is that the roller rockers, at least the Scorpions, have a trunnion with a flat side and an sharp side. The flat side should face up against the polylock.

 

[mrgmhale]

As it's my first engine completely disassembled, well, I have to do it the other way around without doing anything stupid.
So I'm going slowly, I've got some literature, I'm gleaning information right and left, and come what may.
I will be a long reassembly, but I prefere that at the end the engine starts.

I have yet to read the responses of my fellow enthusiasts, so the following "may" have already been said. If it is repetitive, my apologies, but you can take as it being important enough advice to listen to and heed. The building and assembling of an engine ought not be looked as a competitive sport in terms of how fast you ought to go. Not at your end of the spectrum. It is best to leave the fast paced engine repairs to the highly experienced racing car crew members in the pits.

- Take your time, think things through between the moments you are reading about any particular step, and the moments you are preparing to execute your next action.
- If you are using a traditional Flat Tappet Cam/Lifters valvetrain, be sure to use an engine oil with Zinc in it. Otherwise you will end up wearing your camshaft lobes down to a nubs, and wearing your lifter contact surfaces into a dished face, very quickly. Zinc is not typically used in engine oil any longer as it fouls catalytic converters, and is not needed for the more modern roller lifters of newer engine design. If your oil does not have Zinc you can use a Zinc Oil Additive. I personally use AmsOil "Z-Rod" 10/30 synthetic engine oil, as its formulation does have Zinc. There are other excellent brands of oil that also include Zinc.
- When you are preparing to install the pistons and connecting rods take the time to slip some rubber vacuum or fuel hose over the connecting rod threaded bolt ends so you do not end up nicking the crankshaft and/or cylinder walls.
- Dip the pistons (with rings installed) into a can of engine oil before installing said piston/rod assemblies into the engine to help ensure adequate oil lubrication for the pistons and rings in the newly honed cylinder walls. You can never get too much initial lubrication for the various moving parts of the engine.
- Follow the installation and break-in instructions of the camshaft and lifter manufacturer carefully.
- Take care to not damage the camshaft bearings as you carefully install the camshaft.
- You will want to prime the oil pump by spinning the oil pump drive shaft manually (while the distributor out of the engine) before you crank it over to fire up the engine. Priming the oil pump will also help get engine oil to the various items needing to be lubricated before initially cranking over, much less running, the engine. You never want to do a dry start on an engine, as it will cause avoidable and excessive wear in the young engine's life.
- If you are not familiar with how to perform Dead Stick Ignition Timing on an engine, please look at my video on the subject in the link below. If you are using an electronic ignition system the technique is similar, except you will be setting the triggering of the collapse of the Ignition Coil's electromagnetic field through visual observation of the stator wheel/reluctor and the pickup coil inside the distributor, as opposed the opening of the gap of the Ignition Points. Getting the initial timing set up correctly will make a big difference with how well (much less IF) the engine runs when you first fire it up.




Have fun, and best of luck to you.

 

[jdomke1]

There are some good books dedicated to rebuilding a 351C. I mostly use as a reference for high end options I’m thinking about. Pros, cons, etc. But still decent details of the process.

 

[jomar1957]

As it's my first engine completely disassembled, well, I have to do it the other way around without doing anything stupid.
So I'm going slowly, I've got some literature, I'm gleaning information right and left, and come what may.
I will be a long reassembly, but I prefere that at the end the engine starts.

Rear main seal one end should stick up out of the block other recessed 1/2 inch same on cap

 

[perryseth]

One of the best things I read was to treat the process with the cleanliness and order that a surgeon would. Have your tools laid out in OCD fashion and keep everything extremely clean. Take your time and remember- YouTube is like the dad I never had- it came in handy for tips like setting timing, piston ring orientation, etc. Lastly- be sure to check oil pressure and I made a homemade oil pump primer out of an old distributor to splash some oil around. Don’t forget your fluids and have extra help putting engine and trans back in. Be SAFE. Good luck!

 

[Manu Mach1]

Plastigauge joke, I mean I am the joke, I did it with the wrong wire (I guess) using 0.007"-0.020" instead of the 0.0020"- 0.0060"...
Btw, the torque for a 4 main bolts is at 105 Ft/lbs, but how many for the smaller ones , on the manual I can't find about the small bolts, and I don't think the torque is the same as the bigger ones.

 

[DAverkamp]

Plastigauge joke, I mean I am the joke, I did it with the wrong wire (I guess) using 0.007"-0.020" instead of the 0.0020"- 0.0060"...
Btw, the torque for a 4 main bolts is at 105 Ft/lbs, but how many for the smaller ones , on the manual I can't find about the small bolts, and I don't think the torque is the same as the bigger ones.

45

 

[Manu Mach1]

With the right plastigauge, I have better results. I found them between 0.0015 and 0.0020", so, I'm good enough.

 

[Manu Mach1]

At the rate I'm going, the engine should be reassembled within a decade, by which time we'll be running on what, hydrogen?
Well, the crankshaft is fitted, I've coated the journals well with Red Lube, and won't forget to put Permatex Supra Black on the rear bearing to prevent any oil leaks. A little progress next week, if I think about it, if I have time, if I want to...

 

[DAverkamp]

At the rate I'm going, the engine should be reassembled within a decade, by which time we'll be running on what, hydrogen?
Well, the crankshaft is fitted, I've coated the journals well with Red Lube, and won't forget to put Permatex Supra Black on the rear bearing to prevent any oil leaks. A little progress next week, if I think about it, if I have time, if I want to...

Looking good. Did you put a dab of silicone on the ends of the seals before you put the bearing cap on?

 

[Manu Mach1]

Yes I did, and a thin layer on the cap