engine problems

[aggielr]

last year i rebuilt the heads, new vavles all new gaskets and all, well now when i run it, i can hear a hissing sound and the coolant has bubbles in it, i can't see any oil in it and there's no oil in the water, so should i be lookin at the intake or heads? i'm thinkin intake, but whata ya'll think?

[robertf03]

i say just keep running it and look at the gauges. If anything its probably a messed up valley pan gasket.

[aggielr]

what about lots of pressure and bubbles in the coolant? i started it, ran for about 45 seconds, and when i pull the cap off, its sprays about a quart of water out under pressure, and i don't know what the fawkin hissing noise is

[StevenAg03]

the head gaskets are bad if the water sprays out of the cap like your explaining. not a hard job but i WOULD NOT continue to run it like it is....

[aggielr]

guess i'll be replacing head gaskets this week

[Graystroke]

I agree, head gasket leak between the cylinder and water jacket. worst case cracked head or cylinder. what's happening is that you're pressurizing the coolant system w/ cylinder compression. If you keep driving it will eventually blow all your coolant out and overheat the motor. Will be worse at Highway speeds/ high RPM's( more pressure) You maybe able to isolate the problem by inspecting the plugs, looking for a fowled plug as a result of incomplete combustion b/c of low compression on that cylinder. Best way to isolate the problem is do a leak down test. This will let you know where to look once you take the heads off. sometimes it's hard to spot. Smell the coolant and see if it has gas in it. I had a blown head gasket and did all the above. Ran fine at idle and slow speeds and would never overheat. once on the highway, all the coolant would blow out through the cap. No bueno.

[aggielr]

well hopefully it ain't a cracked head, just a bad gasket, last year when i put all new valves in it, they checked 'em for cracks and all, not goin to rule it out, but probably just replace the gasket first, see if that fixes it, probably start on that tommorow so i can drive it by thurs

[fbronco86]

the bubbles are from caviation that could come from alot of things. and since you ran the motor for 45mins yeah i would think if you took the cap off water would come out its under pressure. I would do a compression check first. that will tell you alot of info with out doing alot of work

[aggielr]

Originally posted by aggielr
what about lots of pressure and bubbles in the coolant? i started it, ran for about 45 seconds, and when i pull the cap off, its sprays about a quart of water out under pressure, and i don't know what the fawkin hissing noise is

[aggielr]

alright, i pulled both heads off, and i can't really see any problems with the gaskets, so now i'm worried, if any of you experts wants to come take a look and see what you think about 'em, please feel free to pm me for directions if you don't know how to get here

[Graystroke]

that's why you do a compression test BEFORE you remove te heads b/c it is sometimes very hard to spot a leaky/blown head gasket. this way you know where to look. I'd look at the plugs if the thing was tuned right and look for a fouled/carboned up plug. does the coolant smell like gas

[aggielr]

anyone think i should replace the head bolts?

and would you use copper spray gasket on both sides of the head gaskets?

[eight]

One time in high school we couldn't get some head gaskets to stop leaking. We even had the heads remilled and the block decked, no fix. We finally put copper coat on both sides of the gaskets and they stopped. That ****s not very expensive so now I allways use that. So do it. As for the head bolts, I've just allways used the old ones.

[Graystroke]

Only if they're stretch bolts. which they should not be.

[Fredo]

Sometimes head bolts are expensive, but I see it as a simple insurance policy. I remember helping Josh Alley put the head back on his six and we ended up breaking a couple of the old ones and he had to replace them.

[aggielr]

an ARP set from summit is about $90, so i'm think i'll go ahead and order 'em, i'm kinda agreein w/ fredo, just hate to have it almost back together, then have to wait for bolts to come in