I am new here and I just acquired a 1980 Yota. My issue is I have fuel in my oil. I have replaced the mechanical fuel pump but it's still getting in there. Is it possibly the carb?

 

Here is my
beauty

 

Well since you eliminated the fuel pump assembly its more than likely a carburetor fault.

Improperly tuned carburetor/rich condition.

Engine miss fires...?

Poor cylinder compression..?

Carburetor leaking into intake manifold..?

I'm assuming this truck has the factory type carburetor..?

Possible AAP diaphragm leaking...?

 

Well I do have the factory carburetor but I am ordering the weber 32/36.. I know the stock carbs are good but I opened it up to see about rebuilding and you could tell there had been someone in it before due to not so to spec modifications. I haven't checked the compression as of yet and yes it will back fire if I get on it. I thought this may have something to do with it being a straight pipe turned up behind the cab with no muffler. I didn't think the backfire was maybe due to carb.

 

Does it seem to run rich? worn rings can also cause fuel in oil, I would do a compression test and leak down.

 

I haven't checked compression yet. How hard is it to change the rings if they are wore? Again, I'm just getting into the mechanic side of things. If I can do it myself I will if not it will go to the shop.

 

Pull the engine to do rings..

 

Ok, I'm going to put the weber on it since I changed the mechanical fuel pump. If the fuel is still going to oil the next thing would be the rings? I heard someone say spark plugs that are not firing correctly could allow gas to leak down.

 

Things that cause fuel contamination in oil:

-Fuel shut off valve not closing when the engine is shut off which basically allows fuel to run down through the carb into the cylinders and past the rings. You can check the fuel shut off solenoid by disconnecting it from the wiring harness and applying 12 volts to the solenoid - it should click open when power is applied to the solenoid.

-Carb float bowl is overfilling. This is a carb adjustment but on the stock carb you should be able to see the bowl level through the sight glass.

-Bad fuel. If you just bought this truck, do yourself a favor and drain the fuel out of the tank and add a FULL tank of fresh fuel. Use regular gas to refill - not mid grade or premium. Higher octane fuels are designed for higher compression engines and actually will NOT burn completely nor efficiently in lower compression engines. Higher octane fuels actually resist ignition until the mixture is fully compressed.

-Failure to ignite mixture. This can be caused by a number of things - bad wires, bad coil, faulty ground, fouled plugs (likely if you are running rich), improper timing and low compression.

-Worn rings. A compression test should give to you an idea of how worn your rings are. All the things above are still possible even with perfect rings, but at far less likely to happen or to be as severe as you are saying. Additionally, if any of the above mentioned has happened over a significant period of time, it will lead to worn rings. When fuel mixes in with oil or goes unburnt in the combustion chamber then it acts as a cleansing agent and washes the cylinder walls of oil (lubricant) which causes heat and friction which cause engine wear. With fuel in your oil you're not only glazing/polishing your cylinder walls, you're also not allowing for the proper lubrication of the rod bearings, wrist pins, crankshaft bearings, camshaft and rockers.

You cannot continue to drive the truck with fuel in the oil - you're asking for problems. Change the oil, run it, change it again. Start with compression testing. Minimum compression is 142psi per the FSM (ideal is around 172psi). If compression is bad - check to make sure the valves are closing properly and that it is timed properly. If those are good then you're digging into those rings. You may have to fix or adjust other things, but you'll need to do all that after the rings anyway.

 

I haven't driven the truck since I discovered the fuel in the oil. I will check all those things to see what I am looking at. After I install my weber I am going to check compression. All in all I still feel like j got a good deal on the truck since I only gave 500 bucks for it. *stay Yota strong*

 

So I got my weber and it's the electric choke. I have the water choke and was wondering how and where do I hook this up on my truck? Thanks guys.

 

I just discovered this unfortunate issue on my 86 22r. Weber 32/36 installed 2 days ago, about 7500 on a rebuilt engine, new head at same time. Mech. Fuel pump even newer. I have a faint smell of fuel in my oil today, grrrr. Also carb is back firing only when I let off throttle to down shift, carb has pressure regulator tried running anywhere from 2 to 4 psi. Does better at about 2.5 but can't get it to stop...yet, Yes it's tuned lean best idle, can't find any intake leaks with carb cleaner. It does have a split muffler but no other ticking exhaust leaks. Any ideas??? Float maybe? Heard this could be but extremely rare for new Weber, (real made on Spain) could it be that muffler? Jets? Elevation here 500ft. HELP!!