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I have a 1993 dodge 5sp manual, my daughter broke down the other day and when i went to pick her up i discovered the left side of the engine covered with fuel as well as the crankcase full to the top of fuel and engine oil.

Has anyone had a problem like this? I believe the front seal has gone in the pump and is leaking fuel into the crankcase, is this correct?

Does anyone know where to purchase a front seal or have any other ideas on the problem?
 

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Check the fuel lift pump, it is on the left side down low on the rear of the block.

Is the fuel on the front end of the block or where the lift pump is located?

I don't know about the front seal in the injection pump, hopefully Greenleaf or Phillip will see this and respond to that. I've not heard of a problem there but that doesn't mean it hasn't happened before.
 

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Are you running an electric supply pump? Fuel inlet pressure should not exceed 18psi at the IP. Over that and the front seal will seep and eventually blow out into the timing case.

Also the diaphram in the stock lift pump can tear and allow fuel into the oil but not without pressure from another source that I have seen.
 

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On a stock engine the pump seal normaly isn't a problem area. That seal normaly will outlive the injection pump. I would look around the lift pump first. Our lift pump is just a standard diaphram style. I have replaced many on gassers for pumping fuel into the crankcase.

BTW I even had to repair a IHC inline six that had blown the oil pan/ valve cover and engine side cover off from the same problem. :rof

When an engine goes over full with a fuel/oil mix you can have leaks you have never seen before.
 

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Thanksgiving Day 2 years ago I lost the front seal on my inj pump and filled the crankcase with fuel. So it does happen. I had the pump rebuilt as it had over 225K miles on it. Month or so ago, I lost the lift pump. It didn't leak into the block, it just lost a check valve and quit pumping. They have a weep hole to allow them to drain outside the block for most failure modes.
 

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They have a weep hole to allow them to drain outside the block for most failure modes.
I have replaced many diaphram pumps that have not leaked out that hole. But they did fill a crankcase up.

Think of that hole as more of an atmospheric vent. It gives the pump a base line of the outside air pressure to base its pressure rate on.

I'll give you an example. On the older blow threw gasser aftermarket turbo systems. They had you tape the vent hole and install a boost pressure reference line to it to raise fuel pressure during boost period.

A blown injection pump seal is possible. I would go after the lift pump first. It is most likely orginal. It is probably at the end of its service life. It is also the easyest and cheapest to replace that could be the culprit.

If it isn't the problem I would still replace it if I removed and had the pump repaired. Just for general principals.
 

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As far as fuel in oil, your cummins engine manual says to not idle the engine for long periods. The engine walls cool down enough that all the fuel does not burn, and thus runs down the cylinder walls into the crankcase. Either high idle your engine or don't idle for more than 10 minutes if engine is already warmed. When starting in the morning, let idle for 30 seconds then go. Try not to idle for longer. All information is from my cummins engine manual.
 

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As far as fuel in oil, your cummins engine manual says to not idle the engine for long periods. The engine walls cool down enough that all the fuel does not burn, and thus runs down the cylinder walls into the crankcase. Either high idle your engine or don't idle for more than 10 minutes if engine is already warmed. When starting in the morning, let idle for 30 seconds then go. Try not to idle for longer. All information is from my cummins engine manual.
this is not going to cause the block to fill with fuel, theres no way that much fuel would get past the rings unless they were shot and it idled for hours it is more than likley either the IP seal of the LP seal
 
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