I've got one motor putting more steam out of the exhaust that the other. Been doing it all season, no obvious problems, good water flow, good compression, no signs of corrosion in the manifold/riser.
Could a head gasket have such a slight leak that it wouldn't affect the compression reading?
Any other thoughts, or am I over-reacting to nothing? Dont want to pull the heads for nothing.
Gary

Are both banks on this engine putting out the same amount of steam?

BT

I have full water jacketed headers. One side always seem to have more steam. If one header flows more. Water will exit with the least resistance.
My setup has run like this at Idle for years.

Hope that helps
Gerry

Unfortunately, it's a single exhaust on the motor. Wet exhausts going into a Y pipe, single outlet, so I cant say if one bank is hotter than the other.
I'm going to look for low firing voltage, chack the compression again if I find anything. Then check exhaust manifold temps with an IR gun. Anything else?
Would a leakdown test show anything more than a compression test in this case?
Gary

Leakdown is the way to go.
You can buy one for less then 100.00 bucks.
Record your readings . Then lator you have something to compare.
Im betting you are ok.

Good Luck
Gerry

Plug reading should tell the story if you are getting water into the combustion chamber. I would do the leak and listen test too... after the plug reading.

BT

Followup:
Only steams after warm up, lightly at idle, increases A LOT at increased rpm.
I've got 1 plug that looks steam cleaned. Compression on all cylinders is 180-185 psi and leakdown is less than 15%. All that sounded like it was going past the rings.
20psi to the cooling system, btw, it's a pre heat so that included exhaust manifolds, (water still in it) did not show bleed down.
The lack of steam till warm (140 degrees) and good compression + little leakdown makes me think it's not the head or head gasket. Although the clean plug sure looks like a head gasket problem.
Could I have a small crack in the exhaust manifold allowing for reversion, and that's cleaning that one plug?
Cam specs 282 duration, 104 intake center, 107 exhaust.
HEP, before I waste a good engine.
Gary

Hey Gary:

Is that duration at .050"? (Reversion on only one cylinder??) Is there no water flow through exhaust manifolds until T-stat opens?

If exhaust manifolds are only pressurized when the T-stat opens, then I vote for a cracked manifold at the clean spark plug. Gotta check them before the head comes off the valve. Maybe it's cracked BECAUSE there is only flow after the T-stat opens.

P.S. Were you at the LOTO Shootout?

I'm assuming that's at 0.050, but doesnt say on the TSB.
There is water flow (drilled 2 1/8" holes in thermostat) and pressure in the block/exhaust manifold at all times. There's also a 10psi bypass if thermostat is closed, goes to the risers after the bypass.
When I pressure checked the block + manifolds, the engine was cool, but got no leakage that I could find.

Oh yeah, definitely was at the shootout. Saw your intercooler at the booth. Very nice work.
Gary

What number plug is clean and what for exhaust, center rise merc?

BT