Gasket replacement??

[Williebeaman]

Hey guys so I got a 88 jimmy tbi 350 it has a small leak on the intake and a small leak on the valve covers both of them. I was thinking of ordering a new edlebrock intake and valve covers cause I like when it looks nice and new. But it got me wondering since I’ll have it all torn apart is it worth going ahead and replace the head gaskets? Do they ever get weaker? Or only fail when something else is wrong? I just want it to be a nice reliable truck something I trust driving 5 hours to the beach.

 

[rampage]

I always say if it’s not broke don’t fix it.

 

[tenderfoot]

I'm always afraid of taking mine to the beach. Salts a B.

 

[nvrenuf]

If the motor is healthy I would not mess with the head gaskets, they are not a “wear” item like valve cover, oil pan, etc gaskets.

 

[diesel4me]

I disagree,head gaskets eventually fail after years of heating & cooling cycles,and factory shim steel type ones will rot away around the coolant passages or the cylinder "fire ring" eventually.
Todays engines with aluminum heads on an iron block tend to need head gaskets sooner due to the different rates of expansion & contraction and the effect of two dissimilar metals creating a "battery" effect and electrolosis..
Diesels head gaskets are under a lot more stress with 18:1+ compression ..

That said,I have not had to replace any head gaskets on any of the vehicles I've owned (other than one I removed one head from to replace a burnt exhaust valve)...and I drove many of them for years ,even commuted 150 miles to work every day and on Saturdays when I lived at home and got a job 75 miles away..most of them had well over 100,000 miles on them too ,and had never had the heads off before I owned them..

I'd only tear the engine down to replace a head gasket that had not failed if you were already "halfway there" and had the intake off to do a cam swap or other internal work...it beats having one fail a week later..the bummer is a head gasket failure often leads to the bearings failing soon after they got contaminated by the anti-freeze,if one has failed and the oil looks like mayonaise and it was driven any distance ,chances are the engine's bottom end will need repairs also..

That is why many mechanics just pull the engine out to replace the head gaskets,and inspect the bottom end--or simply get another engine from a salvage yard..

Overall head gaskets on older Chevy SB and BB don't fail often as long as they aren't decades old and the head bolts are kept torqued to the proper specs..the 1973 307 V8 I put in my van still has the original steel shim head gaskets far as I can tell,and I will be leery of one failing if it ever sees road use again..36 years is a long time,and I'm betting the steel is rotted by now in spots,especially after I let it sit 10+ years and only start it up a few times a year..it even still has the original AC fuel pump on it...wont trust that as far as I could throw it either!..

 

[imiceman44]

Hey guys so I got a 88 jimmy tbi 350 it has a small leak on the intake and a small leak on the valve covers both of them. I was thinking of ordering a new edlebrock intake and valve covers cause I like when it looks nice and new. But it got me wondering since I’ll have it all torn apart is it worth going ahead and replace the head gaskets? Do they ever get weaker? Or only fail when something else is wrong? I just want it to be a nice reliable truck something I trust driving 5 hours to the beach.

I am from the camp of if it ain't broke don't fix it.
Now if you're halfway there and you want to do it, remember you also have to take the exhaust manifold off so more gaskets to change.
Not mention the accessories that are bolted to the heads that you need to remove

 

[Williebeaman]

Hmmm thanks guys. I was told it’s the original engine when I got it but who knows. It’s for sure been rebuilt cause it’s painted (not very well) so I’m assuming it’s been rebuilt at some point. She doesn’t smoke and runs good for me as a daily driver. Maybe I’ll leave them alone and just do the intake and valve covers for now. My goal for this truck is not to have a perfect restored truck but I wanna trust it to drive anywhere at anytime.

 

[diesel4me]

I keep a tube of Aluma-Seal powder in my truck "just in case" I get a sudden radiator,heater core,freeze plug or head gasket leak...it is the only sealer I've used that actually works and does not plug up the heater core..

Speaking of freeze plugs,I have replaced many sets on engines I was installing BEFORE I put the engine in,and many were paper thin or already weeping --for the $15 it may cost for the whole kit to replace them all (brass ones are also available at extra cost),it is well worth doing them,they tend to fail more often than head gaskets do around here..some of them suck to get at with the engine installed--like the ones behind the flywheel!..one is behind the motor mount on a SBC too..

Usually a head gasket gives you some advance warning before one fails,you'll see white smoke out of the exhaust on a cold startup ,you may feel a cylinder doesn't fire right after starting cold,and you may notice the oil on the dipstick looks like mayonaise if coolant gets into the crankcase..it's "worse" to have coolant get in the crankcase,engines that blew a head gasket and only lets a small amount of coolant escape into the exhaust may not show any major symptoms for a long time,but you'll be tipped off by having to add a little coolant once in a while..

Having a AAA subscription isn't a bad idea when you own an older vehicle. I should have it but didn't renew it after not using it for a few years..and wish I hadn't now...had the "gold" plan with unlimited towing,which now you cant qualify for unless you've been an entry lever subscriber for at least a year..

 

[HankScorpio]

Fix the leaks, leave the rest. Drive the heck out of it.

 

[big pappa b]

don't touch them