VP 30GS MWTR Intake-Exhaus tmanifold pressure test or just visual inspection

1999 Glastron GS185SF with VP 30GS MWTR motor.

Still playing with the more sudden poor or dies at idle, lack of power performance on the lake, issues of my motor. Fresh gas, full bottle of seafoam in each tank full and still no luck. I installed an inline fuel-water separator filter this fall and it didn't seem to help my situation.

I suspect I may be pulling some water to my intake side of the intake-exhaust manifold on my VP 3.0 4 cylinder motor, as I have seen wet plugs, but just not 100% sure if it was gas or water.

I saw in the VP service manual that you can pressure test the V6/V8 motor manifolds, but I saw nothing on pressure testing the 3.0 4 cylinder manifolds. Is this because it is not possible to do this with this motors manifolds or is this just an omission from VP?

Or do you need to fall back on a 'remove and visually inspect' for cracks or maybe the outlet gasket.

Appreciate any wisdom.

Best Regards,
Brent.

Re: VP 30GS MWTR Intake-Exhaus tmanifold pressure test or just visual inspection

Being a fresh water boat, I'm not sure why you suspect you have manifold problems. Exhaust manifolds on FW boats seldom go bad. Is there some reason you suspect the manifold? Do you show signs of water anywhere?

Did you ever try putting new spark plugs in it? They do die at times, even if they look good.

Re: VP 30GS MWTR Intake-Exhaus tmanifold pressure test or just visual inspection

as I have seen wet plugs, but just not 100% sure if it was gas or water.

Click to expand...

Ayuh,... Unless ya also see Rust,.... It's gas....

Sounds like ya got a Carb problem to me...

Re: VP 30GS MWTR Intake-Exhaus tmanifold pressure test or just visual inspection

the reason I am possibly suspecting an issue with the manifold is I did have the impeller also go out on me and I overheated to maybe 220 on the temp gauge. Once cooled on the water, didn't seem to run any differently before I was towed off the lake. Rough summer for boating and it all ended early.

So no rust as I initially worked on it this in early summer, but 2 of the the plugs were intermittently wet.

I left the boat sitting in the garage from July to Sept-Oct timeframe (real bummer, but busy summer doing other stuff...) before I got to look at it again, and plug #4 did have some rust on the electrode. I have been told that could be due to the exhaust valve being open as the motor sat, and water being in the exhaust jacket the entire time as it was not drained until I winterized it in Oct.

Compression is real good at 150-170 each cylinder.

Hoping it's just carb troubles.
B.

Re: VP 30GS MWTR Intake-Exhaus tmanifold pressure test or just visual inspection

1. Did you change the spark plugs?
2. Did the engine ever diesel (run on) when you shut it off? That's a BIG reason for water in the cylinders.
3. If you had an overheat, install NEW OEM riser gaskets per the instructions.
4. Do you have a water separating fuel filter, and if you do, have you ever found water in it? Have you checked?
5. You mentioned in an older post that you was going to rebuild the carb. Did you? Did it change how the engine ran?
6. Did you change the fuel filter in the fuel pump?

If you answer these, it may just help you get your engine running right.

Re: VP 30GS MWTR Intake-Exhaus tmanifold pressure test or just visual inspection

Don
Thanks for your reply again.

1. Did you change the spark plugs?
I have cleaned them up with brake cleaner and they are like new, and have also changed them once, with no effects one way or the other, other than momentary.

2. Did the engine ever diesel (run on) when you shut it off? That's a BIG reason for water in the cylinders.
Never dieseled when shut off that I can recall, so that is a ray of hope.

3. If you had an overheat, install NEW OEM riser gaskets per the instructions.
Good advise and Ill follow it. Are you talking about the square gaskets between the intake-exhaust manifold and first riser, or the round tube mating pieces?

4. Do you have a water separating fuel filter, and if you do, have you ever found water in it? Have you checked?
Have not changed or checked this yet. Still formulating my plan. I will check and replace.

5. You mentioned in an older post that you was going to rebuild the carb. Did you? Did it change how the engine ran?
Not yet, but its on the list of things to do shortly.

6. Did you change the fuel filter in the fuel pump?
I did this when I bought the boat in summer 09 as remember trying to get the clip back over the pump. Maybe should do it again for insurance. Almost forgot it was there.

Re: VP 30GS MWTR Intake-Exhaus tmanifold pressure test or just visual inspection

1. Put some new NGK or AC spark plugs (no champions) gap them correctly. Can't believe you keep cleaning old plugs.

3. The gaskets between the exhaust manifold and the riser. One on each side of the plate. Do IT NOW.

4. Then pull it off and look. Replace with new if the old one is clean. NOW

5. Then you still don't know if it looked dirty and correded inside, DO IT.

6. That one depends a lot in what you find in 4 & 5.

It's time to stop typing and questioning, and start doing.