Fuel Dilution... 9% !!!!

[davey8943]

SS members!

I had noticed that the multi in my 1969 Kaiser Jeep had been "creating" oil lately. I had a sneaking suspicion that somehow fuel was making its way into the crankcase.

So, I went to the local NAPA store, and picked up an oil analysis kit (~15 bucks). I sent it off and three weeks later....

NINE PERCENT FUEL DILUTION!

YOWZERS!!

So it sounds like there are only a couple of places that fuel can get into the crankcase, and they all involve the Fuel Pump.

I won the truck from GL in March of this year, and received it in early July. I have not changed anything about the FDC. I am not sure if "bypassing it" is an option. Are there any negative impacts to the FDC if it were to be bypassed?

I have read that there are other places, internal to the pump, that can leak. Are these pumps re-build-able? By a shade tree mechanic? If so, are kits available with the right seals and such? Or is finding a drop in replacement going to save time and trouble?

I don't think that "doing nothing" is a long term option. I had meant to do some work with it in the coming months, but am not sure exactly how much damage this can do. Does anyone have experience with an engine that has had long term exposure to high amounts of fuel dilution? I am mostly concerned about the damage fuel will do to bushings / bearings / etc.

Screen shot of the oil analysis attached... I will try to post the whole pdf tomorrow.

**edit** the screen shot is worthless. I will get a pdf up in the morning!

Thanks for all of your help!
Dave

 

[gimpyrobb]

Nope, your better off bypassing it. Get a pic of the IP and we can tell you how to proceed.

 

[FireFighterHill]

Look up FDC or FDC removal you will find a WEALTH of information about what the FDC does and does not do. There is alot of misconceptions about it. If it is not already bypassed that would be my first step to fixing your problem.

 

[WillWagner]

If you post a link to the FDC byp thread here, I'll make it a sticky

 

[davey8943]

I finally got a chance to get some work done on the truck this weekend. I took Gimpy / FireFighterHill's advice and went ahead and bypassed the FDC. Thanks guys

I simply pulled the Tee off of the back of the FDC, plugged it with a pipe plug. Then pulled the drain off the side of the FDC, and plugged it with another pipe plug. I ran a new poly-line from the filter head to the HH, and swapped the Tee at the front of the pump for an elbow. (and took a couple pics because I know how you guys love it!)

It really would have been a quick job, but I took a couple trips to the hardware store!

I took it for a drive, to get the oil warmed up and mixed well before dumping and refilling. Now to keep a close eye on the oil level to see if it still creates oil...

Dave

 

[davey8943]

Digging this one up again... I'm sure it won't take a psychic to figure out why... a few months after bypassing the FDC the engine oil level started raising again

So I did some research and found that the two O-rings under the HH could be culprits. I found a post where Gimpy (thanks by the way!) posted the sizes. I also found a couple of good posts about changing the HH head.

So I changed the two under the HH (with a couple Viton rings). Still creating oil. It turns out I forgot about the o ring under the stop lever! Whoops!

I went back and changed that with an off the shelf o ring from the local hardware store, I have absolutely no idea what material it was (maybe Buna-n?). This is where the story ended for the better part of ~6 months.

Now I am leaking again! So I have two questions:

1) What size is the o ring under the stop lever ? (I will order a Viton replacement)
2) What kind of seal is behind the booster pump? Where can I find one of these seals?

Thanks for the help so far, I am SOOOOO close to getting this thing FIXED!

Dave

 

[scoutmanadam]

just wondering if you have also taken a look at your intake heater, they are known to leak fuel as well

 

[davey8943]

Scoutmanadam,

Good idea, but that was one of the first things to go.

It actually started leaking fuel externally so I ditched it shortly after I picked the truck up from GL.

Thanks for the thoughts!

Dave

 

[doghead]

Your boost pump may be leaking fuel into the oil. Pull it out and turn on the in tank pump and watch for leakage around the shaft.

 

[m-35tom]

the seal on the booster pump shaft is a very overlooked culprit, and can dump a LOT of fuel in a short time. should be about a $6 seal.

tom

 

[davey8943]

DH / m-35tom,

I have been doing some researching, and some figuring..... (which one is more dangerous is a toss up!)

It looks like there are a couple of ways to remove the booster pump (pull the front mount bolts and shift the engine, or pull the entire IP). Neither of these sounds like a lot of fun; but the engine shift sounds like much less of a hassle.

I took a brief look at the clearances, and it looks like the radiator moves with the engine (correct?) and if so, there is only 1-2 inches of clearance (left to right).

Is that really enough to pull the pump? The shaft on the pump looks like it is easily 3-4 inches long.

What am I missing here?

Thanks!
Dave