problem found: head gaskets rotted out around water jackets

[weider1717]

Anyone else have this problem? I have an 87 that suddenly developed a problem I was right to assume head gasket wit the issues but it wasn't "blown" the factory gaskets are all metal and just rotted out.

any advice on head work such as a 3 angle valve job?

also not all gaskets are created the came advice on best gasket set to put on? Seems everyone looks felpro?

[Rickysnickers]

I've always used Felpro head gaskets and never had an issue.

[johnwaynejeep]

It does not seem normal for a head gasket to just rot out. Look at the tops of your pistons, are they clean of all carbon deposits? If they are, then you did have a blown head gasket which could explain the rotted out gasket. Also check your head and engine deck with a straight edge and make sure it is not warped.

When you go to get a new head gasket, you should look for a Teflon or composite head gasket. These gasket types are better for iron blocks and iron heads because they can seal to a rougher surface texture. As far as RTV goes, read the instructions, you typically do not use RTV with head gaskets, but the manufacturer should specify whether to use it.

If you have aluminum heads then go with an MLS style gasket that will allow for expansion between the head and block. You may have to get the heads honed to a finer finish for the MLS gasket and never use RTV on an MLS gasket.

you can also use a graphite head gasket but they are expensive and never use RTV on them.

I hope this helps and if the gasket manufacturer says anything different, go with what they say. As far as the guy behind the counter at the parts house, it's a crap shoot as to whether they know what they're talking about.

[weider1717]

Originally Posted by johnwaynejeep

It does not seem normal for a head gasket to just rot out. Look at the tops of your pistons, are they clean of all carbon deposits? If they are, then you did have a blown head gasket which could explain the rotted out gasket. Also check your head and engine deck with a straight edge and make sure it is not warped.

When you go to get a new head gasket, you should look for a Teflon or composite head gasket. These gasket types are better for iron blocks and iron heads because they can seal to a rougher surface texture. As far as RTV goes, read the instructions, you typically do not use RTV with head gaskets, but the manufacturer should specify whether to use it.

If you have aluminum heads then go with an MLS style gasket that will allow for expansion between the head and block. You may have to get the heads honed to a finer finish for the MLS gasket and never use RTV on an MLS gasket.



you can also use a graphite head gasket but they are expensive and never use RTV on them.

I hope this helps and if the gasket manufacturer says anything different, go with what they say. As far as the guy behind the counter at the parts house, it's a crap shoot as to whether they know what they're talking about.

thanks, i think I have decided to go with felpro "permatorque" head gaskets, any thoughts?

[johnwaynejeep]

Fel Pro makes quality products and the PermaTorque line has all different types of head gaskets. This should work out fine, just follow the instructions in the box for prepping the surface. Keep in mind that a lot of head gaskets are one time use and cannot be reused once they are torqued, so don't miss a step. Also, not all vehicles require replacing the head bolts, but it has become an industry standard to replace them to avoid confusion between reusable and one time use bolts.

[weider1717]

Originally Posted by johnwaynejeep

Fel Pro makes quality products and the PermaTorque line has all different types of head gaskets. This should work out fine, just follow the instructions in the box for prepping the surface. Keep in mind that a lot of head gaskets are one time use and cannot be reused once they are torqued, so don't miss a step. Also, not all vehicles require replacing the head bolts, but it has become an industry standard to replace them to avoid confusion between reusable and one time use bolts.

All good info and I appreciate you taking the time to help me John. To be honest I am lost still I plug in the info on summit racing for a chevy, gen 1 (i assume mine is ) etc and it brings up a TON of head gaskets that are fel pro many having different thickness and bore size and I am not sure of the best option. see example below of one option and there are many many more.

what would you recommend as far as reusing my original head bolts? I took them out gentle not messing them up and this is the first time it has been apart thing is I have no clue if they're a one time torque bolt or a "torque to yield" bolt which SHOULD be good to be used again. It is a 1987 silverado 350

https://www.summitracing.com/parts/f...make/chevrolet

[cadillac_al]

I think gaskets can rot out in 30 years with little coolant maintenance. I have never had a problem using steel shim head gaskets (fel pro). If you use thicker composite gaskets that look superior you will increase your quench and lose a little compression. It probably won't be noticeable from the seat of the pants so it may not matter. I would spray some Hi Tac on a steel shim gasket and be good for another 30 years.

A valve job is always nice but for what it costs you could be buying new heads (almost).

[weider1717]

I would show a picture of the original gasket but this site is awkward about uploading pics it needs a url. If I could you guys could let me know if it was a steel shim gasket or not.

[Pontiac1976]

The gaskets can and will rott out ( same as frost plugs do ) if your coolant is to old it start to eat at the coating on the head gaskets frost plugs. In 87 was a bad year that mostly the V6's head gaskets/intake gaskets. If you go this long you did good & when't way passed the Factory service time.

[johnwaynejeep]

Weider,

Cadillac Al seems to have some real world experience with these head gaskets, I would go with his recommendation of a steal shim head gasket.

Always keep the old gasket so you can compare the new one. You want to make sure that the new one has all the same passages and notch's in it.

You can also take the old one into the parts store and compare the construction of the new one to the old one to see if they seem similar in thickness.