Installing used 351C, tips on internal cleaning

[Monterey]

Hello All,

My recently purchased 71 Mach 1 originally came with a 351C 2V "H" code engine but it is long gone.  I've found a donor 71 Mustang, with the same 351C 2V "H" code engine with about 70K original miles on it.  I've driven the donor car and it seems to be a perfect fit for my Mach 1.  No smoking, exhaust tips are fairly clean, no noises from the engine, runs smooth.  Oil looks respectable and no oil in the radiator.  Next in line is a compression check and if all looks good there I'll pull it and put it in my Mach 1.

My plan is to pull the motor, put it on an engine stand and replace the valve cover and oil pan gaskets, water pump, oil pump, thermostat, possibly the intake gasket.  Carefully repaint the motor and accessories and reinstall.

1. Should I attempt any sort of internal cleaning using a commercial product to loosen up any sludge or deposits before pulling it out of the donor?    

2. Should I replace the crank seals or would I have to pull the crank to do so?

3.  Anything else obvious that I may want to do?

I've rebuilt many an engine but I'm trying to do this on a budget since I may end up "flipping" the Mach 1 to make a few dollars to put into my 73 vert.  There is a slight chance I may hold on to the car but I need to get it running and moving to keep the queen of the castle happy.

Thoughts?

Scott

 

[Ron Tanzi]

You really will not know what level of cleaning will be required until you pull the valve covers and oil pan off. It might be fairly clean or it could be a sludge bomb. To do a rear main seal you have to remove the rear main cap and loosen the remaining main caps (to lift crank) to remove and replace the lower half of the seal. If your rear main was not replaced it will still have the original rope type seal which has a pin in the main cap that MUST be removed and sealed with silicone to facilitate the installation of a neoprene seal. If it looks pretty dry back there I would leave it alone.

Best, Ron

 

[delawarebill]

ron is right on the money.. u don't know until u have a good look inside. if all looks fairly good then clean pan, and i'd pull intake and look there too. and yes it's Sooooo much easier to replace the crank seals now and u'll sleep better and be less then 10 bucks out of your pocket. up to u weather u pull heads or not but the compression test will help figure that out. now with a budget and motor looks good except for goop and piston walls look fine. u can pull engine all apart and pressure wash and blow out lines with air compressor. so everything really depends on what it looks like inside..

 

[boilermaster]

Monterey,

What you plan to do is a good thing.

when you have the engine on the stand you could also remove all of the spark plugs and take a peek at the combustion chambers as well.

That could tell you a lot more about the internal condition of your engine.

when you have the oil pan off look for valve seal pieces in the oil pick-up screen

look for oil/ carbon deposits on the valves.

with the rocker covers off, one can compress the valve springs and check for play at the valve guides.

check the timing chain and timing gears, if you have an oem nylon gear it should probably be replaced.

these checks should tell you if the cylinder heads should come off.

if all looks good, I would clean the combustion chambers with top end cleaner after you have it running.

I always liked to use GM top engine cleaner in my fords, seemed to get the best results.

it can be introduced via a tee at the pcv valve and/or thru the carb venture.

expect lots of smoke.

 Boilermaster

 

[Hemikiller]

Don't do an internal cleaning. You never get it all out and it'll end up in a lifter or somewhere worse.

Highly recommend replacing the timing chain if it's still the OE nylon cam gear unit. They'll fail at the worst possible time.

 

[midlife]

Don't even open it up (except maybe valve covers). You can end up with an extreme case of While-I'm-at-it-itis, which can get very expensive very quickly. If it ain't broke, don't fix it.

 

[OzCoupe72]

I'd be inclined to mostly leave it alone apart from the crank seals and timing chain

Once you open it up and do a half clean you will loosen particles that will find their way into areas you don't want them

A good wash on the outside, a few seals, gaskets, timing chain and a paint rebuild should do it

 

[Monterey]

Don't even open it up (except maybe valve covers).  You can end up with an extreme case of While-I'm-at-it-itis, which can get very expensive very quickly.  If it ain't broke, don't fix it.

I'll admit I've got major fears of catching While-I'm-at-it-itis.  I can see me not stopping until I have the whole thing redone.  I think I've got to figure out a "conservative" approach!

Scott

 

[Monterey]

I'd be inclined to mostly leave it alone apart from the crank seals and timing chain

Once you open it up and do a half clean you will loosen particles that will find their way into areas you don't want them

A good wash on the outside, a few seals, gaskets, timing chain and a paint rebuild should do it

I think it's a good plan.  Just have to hold myself to it!

Scott

 

[Ron Tanzi]

I should have mentioned the timing chain being very important to look at too. If it has the original nylon cam gear replace it. But as others have mentioned the "while you are at it" thing is a problem I have as well. I would end up doing a complete rebuild as I have done in the past. Best of luck. By the way are you going to part out the donor car?

Ron

 

[Monterey]

I should have mentioned the timing chain being very important to look at too. If it has the original nylon cam gear replace it. But as others have mentioned the "while you are at it" thing is a problem I have as well. I would end up doing a complete rebuild as I have done in the past.  Best of luck. By the way are you going to part out the donor car?

Ron

The donor car was pretty well picked over when I got it!  Here's what's left.     I'm going to pull the steering column and a few other minor things but hate to see those quarter panels go to the scrap yard.

Scott

 

[Carolina_Mountain_Mustangs]

It was mentioned about the pieces of the valve stem seals in the pick up screen on oil pump. If you pull the valve covers and the valve stem seals are breaking apart you need to change them. You can do without pulling the heads. When enough of the pieces get on the oil pump screen it will suck up and the hole in the screen will let the pieces into the oil pump and will lock up the by pass valve and explode the oil filter. Then you have to pull the pan and fix. It can also break the oil pump drive shaft if the rubber pieces get in the oil pump gears.

They crumbled after 15 years so I am sure they are in that engine if it is truly an non rebuilt engine. All easy to fix now but much harder when in the car.

My 2 cents,

David

 

[Monterey]

It was mentioned about the pieces of the valve stem seals in the pick up screen on oil pump. If you pull the valve covers and the valve stem seals are breaking apart you need to change them. You can do without pulling the heads. When enough of the pieces get on the oil pump screen it will suck up and the hole in the screen will let the pieces into the oil pump and will lock up the by pass valve and explode the oil filter. Then you have to pull the pan and fix. It can also break the oil pump drive shaft if the rubber pieces get in the oil pump gears.

They crumbled after 15 years so I am sure they are in that engine if it is truly an non rebuilt engine. All easy to fix now but much harder when in the car.

My 2 cents,

David

Thank you David for sharing that with me.  I'll be sure to keep an eye out for them and it sounds like an easy fix.  The while-I'm-at-it-itis now has me wanting to pull the heads "just to take a look" but I'm afraid what I might see! 

:jawdrop:

Scott

 

[mach71351c]

Pull the rear quarter window regulators from the parts car.

 

[Ron Tanzi]

I should have mentioned the timing chain being very important to look at too. If it has the original nylon cam gear replace it. But as others have mentioned the "while you are at it" thing is a problem I have as well. I would end up doing a complete rebuild as I have done in the past.  Best of luck. By the way are you going to part out the donor car?

Ron

The donor car was pretty well picked over when I got it!  Here's what's left.     I'm going to pull the steering column and a few other minor things but hate to see those quarter panels go to the scrap yard.

Scott

Definitely save that steering wheel there are people looking for those.  You are right though it is pretty picked over. Ron

 

[73pony]

Any chance you can take a look at the parking brake assembly? Mine has a few teeth that are worn down and it doesn't want to hold all the time.