head gasket question-200

[Timnmelinda]

Ok the Mustang may be sold, but the possibility of Me getting the engine I got a few months ago (68 200 1970 head supposed to have less than 10k on it since rebuild)......I want to pull the pan checking out the bottome end, and I am thinking I should pull the head to see what the top end looks like, I am thinking we do not want to go through the work of the swap if the engine would not prove to be tight.

So if I pull the head, what should I do about a gasket......It has been posted many times that todays gaskets are thicker and will cause a loss of compression that would be noticable, I know Mike has thinner gaskets coming but they are not here yet.......so what should I do?

Pull the head, leave it be. I want this to be right if we do it, I want the purchaser to have something nice that he can rely on.

So what should I do?

Tim

 

[BUZZ]

That's a hard question. If you pull the head and put a stock head gasket back on it will just lower the compression a few points on a stock none rebuilt engine. That being said, this motor has already been rebuilt 10k ago so the stock head gasket is long gone already and the compression is already lost. So if you pull the head and put a new head gasket on your not really changing anything. On the other hand you could have the head milled to get back the lost compression, or wait for a thinner gasket to be made. The thinner gasket would be the way I went, but I wouldn't want to leave a motor opened up for a long time. I like to close them back up as soon as I can. I really don't know thats a hard one. No telling when the new gaskets will be ready

 

[page62]

You're creating too much work for yourself! Leave everything be. Sell the car as it is. Offer the engine to the buyer of the Mustang. If they don't want it, sell it separately to help recoup some of your money.

After all, who knows? The person who wants the car may be planning on doing a V8 swap anyway...

 

[ludwig]

What he said. It's not a lemon, it's a 40 year old classic.

 

[Timnmelinda]

The person that is interested in the car wants to pay extra money to go ahead and have the newer engine put in, Along with the 8 inch rear. IF I think the engine checks out.
Yes it is more work, BUT It is also for a higher price, and If we do it, I wish for it to be decent.....I have sold many cars to get out from under them and problems.......This Mustang is different, it was built trying to do everything right, as I figured my daughter would wish to keep it for a long time and if a higher price is going to be paid for the newer engine going in then I want that to be right as well.......
I do not know when Mike will have the thin gaskets available, But I do not believe the purchaser or myself wish to wait longer than we need.

I also do not believe getting the head machined would be in his budget, And allthough I will give much, I do not want to pay for that on top of it all.

So I am still torn as to what to do, If I run a modern thicker gasket, how much difference will it be in the general performance of the car?

 

[grocery getter]

since your set on doing this. drop the motor in and do a compression check. run it.... it doesn't take much time. pulling a head and looking isn't going to tell you as much as a compression check and firing it up.

 

[Bort62]

since your set on doing this. drop the motor in and do a compression check. run it.... it doesn't take much time. pulling a head and looking isn't going to tell you as much as a compression check and firing it up.

+1

 

[page62]

The thinner/thicker gasket isn't going to make that much of a difference in this case. Within a nominal range, there's about a 4% performance difference for every point of compression lost or gained.

There's a dealer on ebay (performance gasket) selling a good-quality engine ROL gasket set for $19.75 + shipping. I used them and found the head gasket was impregnated with a sealer. Good quality! Given the leakage issues these engines have, this is more important than the thinnest gasket possible.

 

[addo]

Tim, can you borrow an engine stand?

I'd suggest starting with the motor upside down, head on. Evaluate the bearings, and if OK, re-torque. Remember to keep the shell backs (and their seats) scrupulously free of oil. Tack the pan back on, but not sealed yet.

Next, flip the engine and examine the bore wear. Measure the bore size, too, and evaluate the piston dish volume.

Head is another matter. Look at the valve seat condition, and valve edge margins. Get a feel for how suitable these are, and then consider measuring the head volume. Check out the exhaust flange, as gasket leaks are all too common.

If unsure on anything, you can always post pictures here.

 

[Anonymous]

I know I never post, but addo pretty much nailed it if you want to "once over" the engine before it goes in. It'll take 30 mins-1hr.

 

[Timnmelinda]

As always, I appreciate the shared input
I am familiar with checking out an engine (Done so many times in the past just not with a ford 6, but principals are all the same)

Just worried about what to do about the head gasket, as I had explained It is the lack of a thinner head gasket I am not sure how to deal with. So I am trying to look for ideas/suggestions about this issue.

I do not want to go through getting head machined to correct for new thicker gasket, I do not know if purchase will want to add those expenses.
So I am trying to figure options to best discuss with him.

As stated I want to know it is pretty much right If we go through the bother of doing engine swap.......Except for some oil burning the origional engine is doing just fine But it will become worse, and noone wants to smell burning oil all the time while they drive either, But I kind of feel it would be better keeping it in, if I can not pull the head and check out the topend of the replacment engine, to better know its condition. It was supposed to be good, but people will often tell you anything to sell something, I trusted the guy, but figured If I checked it out and it was not fresh/correct I would rebuild.......But now that I am selling the car I am not going to go through a rebuild.

Tim

 

[BIGREDRASA]

Pull the head, examine head and cylinder bores, and reasssemble with a new, quality gasket. I had another thread trying to instigate some "heated" discussions on the balance between higher compression or greater spark advance. The concensus seems to be that slightly lower compression will move your peak torque/horspower a little lower in the RPM range, and the ability to add advance will make up in part for the lost compression. The car will feel peppier in daily driving, and be better able to tolerate lower octanes. Just KISS the problem away! 8)

 

[Bort62]

Do a leakdown test on it. If you don't get air rushing into the crank case, cooling passage, intake, or exhaust - your probably in pretty good shape.

But I will warn you that you are getting into a can - o - worms selling a car w/ an engine you JUST put in. Now, instead of some guy selling a car, you are selling your services... which means you just made your self a mechanic. As such, people have certain expectations about the quality of your work. Be prepared for him not to be happy with the install you do / run quality of the engine (and everything will end up being your fault).

If you really want to swap this crap in before you sell, then swap it all in and THEN advertise it. Otherwise, sell it seperately. You will make more that way anyways.

 

[grocery getter]

if the engine only has 10k on the rebuild, it likely already has the thicker gasket. if it does you still won't know much until you cc the head.

 

[BIGREDRASA]

You're going to worry yourself to death. Just concentrate in making sure everything is put together correctly, and let it go. Don't become #3.

scrupulous, adj.
5< MFr or L: MFr scrupuleux < L scrupulosus6
1 a) extremely careful to do the precisely right, proper, or correct thing in every last detail; most punctilious b) showing extreme care, precision, and punctiliousness
2 extremely conscientious
3 full of scruples; hesitant, doubtful, or uneasy, esp. constantly and obsessively, in deciding what is morally right or wrong

 

[page62]

There seems to be a consensus building here: Just do it! (and don't worry about the gasket thickness...)

 

[wallaka]

I concur. Don't worry about it; I promise you won't be able to tell a difference.

 

[Timnmelinda]

Ok thanks to all
I really just did not know the difference it would make with the thicker gasket, so now I know

Thanks

Tim

 

[JackFish]

Ok thanks to all
I really just did not know the difference it would make with the thicker gasket, so now I know

Thanks

Tim

I think the point is that it won't matter to you once the car is gone.
And how much it needs shaving determines how much it will cost.
Might not cost as much as you think. 5 thou might cost...$50... for arguments sake. And if you could find a thin head gasket I'm sure the seller might want a number approaching that.
That decision can be left up to the buyer.