mrh12000

This is the car that just wont quit with surprises.
65 396 fresh build, very low hours, and i start it up there is a big cloud of steam from one bank. ran it till it cleared up and no smoke or steam. start it a couple of days later and no steam, no indication of blown head gasket either.
Have the exaust out to pull trans, and see its slowly leaking coolant from one of the exhaust manifolds (driver side), so like a cylinder is full of water (it did seem to hydraulic when i last started it to the could, but not think of that at the time). I'm thinking maybe intake gasket? Maybe head gasket? Any other ideas (ones that dont include suicide)?

Boyan

Hard to understand your post. Did you have hardened valve seats installed in the heads? Why dont you pull a plug and see what cylinder might be involved?
Boyan

65tripleblack

Pull all the plugs on the involved bank. The clean one(s) are from the cylinder(s) with coolant leaking.

If it's as Boyan mentions, with leaking exhaust seat(s), then you should have the leaky seats pulled and sealed before you crack a head.

mrh12000

its when it has been sitting for a couple of weeks the cylinder must be filling with coolant somehow

narlee

Don't try to start it again before it is corrected you could do some serious damage.

MikeM

If you suspect that, pull the plugs out of it on that bank before you start it next time. Water will either run out or blow out when you crank the engine. Simple.

Tampa Jerry

When you get it sorted out, don't for get to change your oil. You could have water in the crankcase. Jerry

mrh12000

thats good heads up too, i will have to check and see if i did any damage last start up.
but the real question is where the leak into the cylinder would be and why it just started acting up
I will try and figure out which cylinder, pull the intake and look at the gasket first. Anybody have experience with intake manifold gasket leaking into the intake runners? Then i will pull the head if I have to.
I really dont know what gaskets the builder used, I usually go with Felpro.
It cant be too bad a leak because it does not act like a blown head gasket, but it is a mystery as to what it might be right now until I can get to it.
Engine has been in a year, and run probably 20 hours.
Its had coolant in it so it should not corrode the gaskets but thats all i can think it would be..

Boyan

Sometimes I wonder why I even bother to try and help......

gibs04

This reminds me of a problem I had several years ago, very similar to yours. My heads were never torqued properly. While hot no problems, when cold dripped water down the sides of the block. I Retorqued everything and never had anymore problems. Just a suggestion..Good Luck..

mrh12000

My understanding is that non hardened valve seats just lose their seating ability, can help me understand how they would contribute to a water leak?
Thanks

MikeM

I think he didn't read what he wanted to read?

mrh12000

are you thinking they cut into water jacket installing the seats? Sorry I did not get it from your question

Nowhere Man

So did you pull the intake? Make sure there is no water in the oil.

Boyan

Well, if you had new seats installed, then yes, they may have hit a water jacket and depending on the position of the valve, it may or may not leak. If I knew what was done, I could tell you the next step, but I will try and guess all contingencies.

You need to isolate the cylinder (s) like stated before, then either pressurize the cylinder or the cooling system and you will be able to track down your leak. If you tear it apart before doing any of this you are chasing your tail.
Boyan

mrh12000

Thanks Boyon, to be honest i dont know if they put in new seats, but a leak there or from the valve guide would probably make sense for the symptom.
i should be able to isolate the cylinder pretty readily from the tips here, and pulling the exhaust manifold too.
I can put a test on the cooing side, should tell me how quickly it loses pressure adn how much of a leak it would be.
when i pull the plugs if a cylinder is full of water that would seem more likely to be a gasket leak, if not then leaking directly into the exhaust port would be more like a seat or guide leak.
There are several products that folks seem to use to seal such leaks, KW being one, im not sure if you would recommend that approach?
http://www.crcindustries.com/files/B...%208-16-07.PDF
i wont get to this for a couple of weeks though, still have transmission to go back in as its on a lift.

Merry Christmas and again thanks this forum is very helpful for me.

mrh12000

well it was a guide leak after all, two of them. The machine shop was able to repair and have first restart today

mrh12000

Avispa

It could also be a leaky valve guide on the affected cylinder(s). The exhaust guides run through the water jacket. Any leaking water can get into a cylinder with an open exhaust valve. The valve seats are usually just machined surfaces in the head casting. If your heads have insert valve seats, it's possible the original seat surfaces were cut through to the water jacket, it's just not very common and most likely isn't what's causing the problem.

mrh12000

The exhaust guides were leaking into the water jacket, the shop replaced two of them with oversized guides. I think these are stepped on the outside diameter and need to go in the right way.
I was lucky the bad one did not hydraulic the cylinder
Total bill from the head shop to skim the head surfaces, replace the guides, grind the valves and replace springs (and machine the guide ends for tighter stem seals) came to like $cdn 1400