88 caprice head replacement?

[kevn83]

I am doing a cylinder head gasket replacement on an 88 caprice with a 4.3L V-6 motor. I blew the head gasket due to a leaking radiator. I had another thread, but it got clogged with other people asking different questions.

I did not do a compression test... as the motor only has 60k on it.... In hindsight it would have been a good idea though.

At this point I have the car apart and the heads are off the car.


One question I have is... when I took the bolts out of the bottom of the heads... water poured out... However, some of the bolt holes had water in them after the heads were removed. Is this normal?

also, 3 studs on the exhaust manifolds broke during removal. They were the studs that connect the manifolds to the y pipe under the car (not in the block). How would one replace these?... I am taking the heads to a machine shop soon.. should I just take exhaust manifolds in to? Does anyone have a ballpark figure ($$ range) for getting heads machined?

[silicon212]

Originally Posted by kevn83

I am doing a cylinder head gasket replacement on an 88 caprice with a 4.3L V-6 motor. I blew the head gasket due to a leaking radiator. I had another thread, but it got clogged with other people asking different questions.

I did not do a compression test... as the motor only has 60k on it.... In hindsight it would have been a good idea though.

The engine would have failed a compression check on at least one cylinder due to the head gasket failure.

At this point I have the car apart and the heads are off the car.


One question I have is... when I took the bolts out of the bottom of the heads... water poured out... However, some of the bolt holes had water in them after the heads were removed. Is this normal?

Yes, this is normal if you did not drain the block ahead of time. There are drain plugs on the bottom of the block - one on each side (the passenger side 'plug' is a knock sensor), that you remove to drain the water jackets. The head bolts are open into the water jackets, so if the water hasn't been drained from the engine, it will issue forth from these bolt holes.

also, 3 studs on the exhaust manifolds broke during removal. They were the studs that connect the manifolds to the y pipe under the car (not in the block). How would one replace these?... I am taking the heads to a machine shop soon.. should I just take exhaust manifolds in to? Does anyone have a ballpark figure ($$ range) for getting heads machined?

Machine shops vary from region to region. Therefore, it is hard to give an educated guess as to what you will be charged. Shop around, but pick reputation over price - in other words, machine shops are one thing where it isn't always economically justifiable to pay the lowest cost. The broken studs can be removed from the manifolds for an additional cost.

[bobss396]

Once you crack the gasket taking the head off the car, coolant goes everywhere, so don't sweat it. Just sop it up the best you can, use a shop vac if you have the wet type. Get into all the threaded holes with a bottle brush and give them a shot of WD40 which displaces water (and coolant). If you have an air compressor (and safety glasses) blow all the holes out.

I agree on taking the heads to a good automotive machine shop. I would inquire about an exchange set of heads, they aren't that much money.

On your own, if you have a good heavy straightedge you can check the deck of the block to see if that surface is good. Which it should be unless you really cooked it. But I'd only suspect this if the engine heat seized. But do run a big flat file over the top of the block surface before you put it back together. Wipe it down with lacquer thinner when you're done.

Manifold studs, my favorite. If you have some of the stud sticking out, you can try a stud extractor or vise grips. A little heat from a torch (the blue wrench) is great, even a propane one will work. Focus the heat on the manifold. This expands the manifold and breaks the ring of crud around the stud. Try this only if you have a sturdy bench vise on hand. Otherwise the machine shop can do it for you. They generally have a flat fee per stud. I'd guess it might run you at least $30 per stud if they have to drill and tap them again.

Bob

[PeteA216]

I removed the broken bolts from my manifolds using vise grips and an ascetolene <-spelled wrong torch. With bolts that couldn't be grabbed with vise grips I used the same torch, a drill, and stud remover found and any hardware or auto parts store.

[kevn83]

I have another couple questions. how do you clean the surface of the block?... The head gaskets left something that looks like soft metal all over the mating surface of the heads and block. I don't want to damage the block surface durring the cleaning process. Can I use a scraper?


Also, I am getting married this sat. so this project is a work in progress.

Another problem that I had was a bolt broke off and was stuck in the intake manifold... it was a bolt that helped to hold the water pump.. it was right next to the thermostat. I drilled out the bolt as the ez-outs did not work...

I tried to retap the hole but it did not work... the tap would catch alittle then give way after about a 1/2 turn or so... I am just wondering how hard it is to tap a bolt hole in cast iron... its 3/8-16. The only thing I can think of is that there is still some of the bolt in there and thats why the tap is not catching. so I went out a bought a thread insert (helicoil). and will drill the hole out larger to get the insert to fit...


I would just like some first hand advice about taping holes so I can get it right. I have an old cast iron motor mount that I think I will practice on. I am assuming the tap should catch in the hole and it should just carve away the threads 1/8 turn at a time. is there any trick to starting the tap?

Thanks for the help.

[silicon212]

I've used an oiled, fine-grit emery cloth to excellent results.

[bobss396]

I like to use a razor blade type scraper, the ones to remove inspection stickers are good. They won't dig in like other scrapers. Wipe it down with carb cleaner and give it another scrape. I always follow up with a large flat file.

As for the manifold, you'd be best off to let a machine shop do it. The tap for a 3/8-16 insert is pretty big, not really a DIY job unless you've done them before. The tap drill for that is a 25/64. You also have to be sure all the old bolt is out or the drill will "walk" and the hole will be oversized.

I usually make up a "guide block" for the drill out of some scrap steel or aluminum and bolt it down if possible to a nearby bolt hole. This keeps the drill straight. Also use a drill stop or put tape on the drill so you know when to stop. Use a little WD-40 for lube.

For tapping, I use a tapping block to guide the tap. Nothing more than a piece of aluminum or steel that is held against the surface of what you're tapping with a hole in it to keep the tap straight. Use a t-handle on the tap.

I'll go a 1/4 turn, back the tap off, go another 1/4 turn, do the same thing. You'll have to blow the chips out of the hole now and then. Use some WD-40 for lube.

To install the helicoil, you need a drive tool, some parts stores lend these or you can buy a package with the tap drill, tap and drive tool.

Good luck to you, and on the marriage thing, don't do it unless she has a ton of money to bring to the table!

Bob

[kevn83]

Hey guys. I just got back from the machine shop. They have not looked at the heads competely, but they said that from first glance it seems that the heads are in good shape and that they probably were not leaking in the first place.

They told me that oil in the radiator is an indication of either tranny fluid in the coolant or a cracked block. I will know more when I hear back from them about the heads, but now I am stumped. Does anyone know what the coolant looks like when its mixed with tranny fluid. is it possible for the oil to only leak into the coolant due to a blown head gasket? The guys at the machine shop kept telling me that there is no oil pressure in the heads...

At this point I have no choice but to put the car back together and keep an eye on it... I do have a new radiator to put in... However, if it was the tranny cooler in the rad. that went would I be able to tell by looking at the tranny fluid? would it change colors? it looks normal but I cannot check the level as the car is apart. How do I get water out of the tranny?

I am really stumped... when I left the goo I got out of the radiator set... it looked like it seperated some and the stuff that seperated out looked like oil. Any help with this problem would be greatly apprecaited.

[silicon212]

Transmission fluid with water looks like a nicely pink strawberry shake.

[kevn83]

Ok, I Got the heads back.. they were warped... High in the middle and low on the ends. They cleaned them up and I will get them back eventually. I will still need to pick up the gaskets, plus one of my other cars is acting up so they needs my attention first... then I leave friday for my honeymoon... so more questions will be coming.. it just may be awhile. Thanks for all the help

Also, the goo in the rad. was yellowish white-ish goo... so I am going to assume that the tranny fluid did not get in the coolant...


However, is there any part of the heads where there is oil under high pressure?

Thanks

[Blue Bowtie]

Originally Posted by kevn83

... I leave friday for my honeymoon... so more questions will be coming.. it just may be awhile.

Umm... no offense intended, but if you have questions about your honeymoon, perhaps you might consider putting off the wedding for a little while.

Good luck. We'll be here when you return.

[kevn83]

can the head bolts be reused on a 88 4.3L motor.... I bought a head gasket kit and I thought it was suppose to come with new head bolts....It did not. Felpro does not even make head bolts for this motor. I will look harder for the head bolts if needed.... I keeping hearing that I am suppose to get new one... but now I hear that since my motor is old (still has cast iron heads) that it should be ok for the original head bolts to be resued.



Thanks for the help.

[inafogg]

yes using the old head bolts is fine,you may want to wire brush them

[kevn83]

Hey guys I have another question... what type of sealant should be used on the threads of the head bolts???

Also, what kind of grease should be used on the pushrod ends? I am assuming regular bearing grease should not be used.

Thanks

[inafogg]

hello kev welcome back hope HM was great
as far as grease on push rods i dont use any
as far as thread sealer again i use none
i have never used any thing but a white lethium could be used on PR
thread sealer could be used but did someone tell u that u needed to??