Sporadic power/throttle performancePCV oil leak

[jarrambidez]

So many things and rabbit holes to go down!! Please help.

Purchased a 2009 Tahoe Q4 with mericruser 3.0l alpha 1 and took to the lake and ran just fine several times. This past trip went and out of no where the performance of the boat changed. Meaning when throttling up it would take for ever to get on plane if ever. Sometimes I could go back to neutral and then throttle up and would be fine. Additiontally while in operation it would vibrate much more than normal and again other times like nothing was wrong.

When shutting down it would knock and shake for a second or two before stopping. So I did some research and I started with the prop, check that out and cleaned out fishing line, replaced the hub and did a water check in the transom oil and all is well. While I was doing this I decided to do regular replacements of spark plugs, ect..

Before starting this, I noticed that oil was on the valve cover in and around the PCV. I did do a visual of the carb and it appears to be really clean no sludge or build up in it but it does smell strongly of fuel (yes I get that fuel goes into the carb). From the research I've done this can be so many things. So in an effort to trouble shoot the best where should I start? Now to be fair it doesnt look like a large amount and oil level seems ok still. but want to get ahead of this if possible or even if I need to look somewhere else first for the performance issue.

1. PCV. Is there a part number? There seems to be a mixed bag of check valve or just an open elbow. If an open elbow is this something I can pick up say at autozone? The replacement should be pretty easy.
With this i see there is are several different ideas and theories of overpressure.

Also side question.. I have a new fuel filter but how the heck do you get to it with out pulling the damn motor!?

 

[Rick Stephens]

Welcome to iBoats.

If I am not mistaken, there is no PCV valve. That hose just a breather that leads to the flash arrestor and is open end to end.

First things to look at with your problems are dump your water separator out into a clear glass container and see if anything but clean fuel.

Being a TKS you may be having an issue with the electric solenoid enrichening system (what makes it a TKS is the carb) I have never owned one of those, but I believe when it is in the rich position for cold starts it makes a hissing noise. If you hear that noise after you have been running and are all warmed up, the valve may be sticking.

 

[jarrambidez]

Welcome to iBoats.

If I am not mistaken, there is no PCV valve. That hose just a breather that leads to the flash arrestor and is open end to end.

First things to look at with your problems are dump your water separator out into a clear glass container and see if anything but clean fuel.

Being a TKS you may be having an issue with the electric solenoid enrichening system (what makes it a TKS is the carb) I have never owned one of those, but I believe when it is in the rich position for cold starts it makes a hissing noise. If you hear that noise after you have been running and are all warmed up, the valve may be sticking.

Ok great thank you. So I was trying to get to the fuel filter/separator but its in a position that is really hard to get to with out pulling the motor. I planned on replacing that during all this. Any suggestions on how to get to it? My owners manual shows a screw on filter as well but I don't see that anywhere either. I was bit frustrated yesterday.

 

[Rick Stephens]

Ok great thank you. So I was trying to get to the fuel filter/separator but its in a position that is really hard to get to with out pulling the motor. I planned on replacing that during all this. Any suggestions on how to get to it? My owners manual shows a screw on filter as well but I don't see that anywhere either. I was bit frustrated yesterday.

Those kind of things are boat manufacturer specific. Snap a couple photos and see if there's a good idea on how to access.

 

[Rick Stephens]

Also note that the flash arrestor screen on the carburetor will clog up with oil and carbon if your motor has even a little blowby. Make sure you check it for clean.

 

[jarrambidez]

Those kind of things are boat manufacturer specific. Snap a couple photos and see if there's a good idea on how to access.

Ill get some pics of where its located here shortly. Also Ill check out and clean the filter too, that makes sense.

 

[jarrambidez]

Also note that the flash arrestor screen on the carburetor will clog up with oil and carbon if your motor has even a little blowby. Make sure you check it for clean.

Bottom front portion of the motor. I can touch it and there is cable protector of sorts on the nut as well seem tgid as usual from factory

 

[Scott06]

Bottom front portion of the motor. I can touch it and there is cable protector of sorts on the nut as well seem tgid as usual from factory

Yes i think there is a safety wire on the bolt losen it back the bolt off. thats actually a lot of room compared to some boats…

 

[Rick Stephens]

That one doesn't look too bad. After you get it clean and determine if there is an issue, you should consider adding a canister fuel water separator before the pump. Then you never have to pull the pump one off again.

If the filter on the pump is dirty, you will also be advised to put a kit in the carburetor and get it clean. I believe there is a filter inside the big nut where the fuel line attaches.

 

[Scott06]

That one doesn't look too bad. After you get it clean and determine if there is an issue, you should consider adding a canister fuel water separator before the pump. Then you never have to pull the pump one off again.

If the filter on the pump is dirty, you will also be advised to put a kit in the carburetor and get it clean. I believe there is a filter inside the big nut where the fuel line attaches.

This is good advice see whats in the filter, probably carb related. Would verify timing is ok as well

 

[jarrambidez]

sorry for the delay. Finally got to the fuel filter.. it’s very dirty. Also little bit of wat looks to be air bubbles in the fuel which is probably water. Going to clean out the filter cup/housing as it’s very dirty too. I’ll pull the filter off in a bit and give an update to the carb thanks again

 

[jarrambidez]

Carb looks pretty clean

 

[Rick Stephens]

Outside of a carb is mostly meaningless. It takes a very small amount of crap to screw up the inside flows.

The gas looks funky in the picture. Might just be the plastic bottle. Needs plugs, filter and carb rebuild at minimum.

 

[jarrambidez]

Fuel is cloudy and some water in there. Got the new fuel filter in. I could only get the inner seal not the out on the fuel pump filter. That said only one came off and I checked for a second. The replacement came with a inner and outer. I could not for the life of me to get it to take the outer.

 

[jarrambidez]

I fired her up and she purred, didn’t run rough, fired up no issues sat ar 8.7-9 rpm temp and oil pressure sat steady and didn’t see any sign of blow back. That said it was just at idle.
I dropped some fuel treatments into it and will let it sit over night and start again tomorrow. Should I put some carb cleaner in there as well? Not sure I’ll get a chance to test on the water till next week.

 

[jarrambidez]

The longer one is just after start up you can hear the hissing the second shorter one is after warm and the hissing is all but gone so hopefully that means the tks is working. I took the filter off to clean it. Also was looking to see if fuel was dropping after running. I do think I need to get the mixture adjusted though.

 

[Rick Stephens]

No such thing as a mechanic in a can. If carburetor needs cleaned/rebuilt/kitted, you take it off, disassemble and clean it. You cannot wash crap out of the carburetor from the outside.

 

[jarrambidez]

Haha ya I get that.