Fuel injection

[Vit]

I am finishing renovation of my car and one problem showed up.

I smell petrol from engine oil and it seems that petrol is in engine oil. Engine start easy, but it no goes to high speed. It immediately start shoot to exhaust and speed of engine go down.

Can go petrol thru injection pump to engine oil or has anybody other idea what is problem and how to fix it?

Thank

Vit
230SL 1964

Vit

[A Dalton]

You may want to check the cold start valve on the intake manifold.  It may be bad and flooding the engine
 Disconnect the wire to it .. there should be no fuel getting past the valve with the engine key on .. It should  only work with the key in the Start position..thy that first and post what you find..

[Cees Klumper]

I seem to recall there was an exchange about this not too long ago, that there is in fact a possibility that fuel can get into the oil via the injection pump. I may be wrong, but that's my recollection. Anybody know for sure?

Cees ("Case") Klumper in Amsterdam
'69 white 280 SL automatic

[A Dalton]

quote:Originally posted by cees klumper

I seem to recall there was an exchange about this not too long ago, that there is in fact a possibility that fuel can get into the oil via the injection pump. I may be wrong, but that's my recollection. Anybody know for sure?

Cees ("Case") Klumper in Amsterdam
'69 white 280 SL automatic

 That would be a more likely possibility on your car than his.
 He has an .042 chassis and they did not use the engine crankcase oil recirculation feed system. They only did that on pumps after R-20.
 His has the oil res/dip stick lube system.

[Cees Klumper]

Right, thanks Arthur.

Cees ("Case") Klumper in Amsterdam
'69 white 280 SL automatic

[ja17]

Hello,
The 230SL injection pumps had isolated oil supply. It is self contained in the injection pump, hence the little injection pump dip stick. Now, fuel can contaminate this isolated oil supply through the injection pump but it will not enter the engine oil.

I agree with ADalton, check the starter valve on the intake manifold. Any rich running condition in the engine itself can allow unburnt fuel to by-pass the piston rings and end up in the engine oil.

Joe Alexander
Blacklick, Ohio

[Vit]

Thanks for all comments.

Car is from 1964 and should have isolated oil supply, but I have oil line to the injection pump. Maybe previous owner changed this pump. I was thinking if is possible that small amount of petrol is mixing to the engine oil in pump and goes together back to engine oil pan and again again.

I didn’t check yet what A Dalton recommended I will try it during weekend and will report it.
Vit

Vit

[Naj ✝︎]

Vit,
Does your fuel pump have a dip stick? It should be on the back of the pump, hidden under the solenoid.
The 230 pumps also have the oil line. Its for lubricating the delivery valves I believe.
This may help:
http://index.php?topic=790,tour

naj


65 230SL
68 280SL

[ja17]

Hello Vit,
All the injection pumps have the metal oil line going from the engine. The isolated versions have a check valve and attach at a different location on the injection pump. On the isolated versions the oil line supplies oil for only the "oil seal" around the plungers. The "oil seal" acts like piston rings for the plungers forming a seal so fuel is compressed into the injection lines and forced through the injectors.

As Naj has mentioned, look for the little dip stick, the most obvious sign of the isolated version. You can also read the serial plate on the side of the pump to identify the "R" identification number of the pump.


View the injection pump dip stick in this photo, it may be in slightly different places depending on the version. It is the unit with the "T" handle and large slot, it unscrews and has a dip stick attached.

Download Attachment: Injection pump dip stick.jpg
58.41 KB

View the different locations that the oil supply line enter the injection pump in the "isolated" and "circulating" versions.

Download Attachment: circulating oil and isolated oil injection pumps.JPG
43.24 KB

Here are three different oil supply lines used on the W113 engines. The "isolated" version uses the one with the check valve at the top.

Download Attachment: inj pump oil lines.JPG
63.75 KB


Joe Alexander
Blacklick, Ohio

[A Dalton]

Oil res. pumps can be distinguished at quick glance because they   have a Filler Cap right on top of the pump .  Can't miss it . The 230 ones had a metal cap and the 250 had a Red plastic cap.. Stamped "Oel" right on top of the cap.
That is where the oil is added/changed...

[Vit]

Hello
Thank for all comments, but I am really confused. I have pump with dipstick, but only with one solenoid. When I screw out dipstick, reservoir was full and black oil went out. I try to check number of pump and find following. On one are these numbers – PES 6KL70/120 R11 bottom 510 147 8 and on lower second plate are R 1/1 ALR/ PE.
Please help with advice.    

Vit

Vit

[rwmastel]

Vit,

You have an R11 pump.  Oil should not flow out, it has been over filled by fuel draining down past the plungers into the oil resivoir.  I recommend removing all oil and replacing with fresh oil, what ever type you use in the motor.  From memory, I think the capacity is about 180ml.  Just put in a small amount, use the dip stick, and keep filling in small increments until the dipstick reads a proper amount.

This can be a difficult task with no drain hole and such a small fill hole.

Rodd
Powell, Ohio, USA
1966 230SL, Euro, Auto, Leather, both  tops
1994 E420

[A Dalton]

You have the correct pump for that chassis [R-11]

 What you want to do is to drain the res completely and refresh with new oil [ I use 30w. motor oil] up to dip indicator line [ do not overfill this pump]

 The cavity is very hard to drain , as it has to be sucked out from the same hole as the dipstick goes in .
 If you have a vac pump . this is easy with a small piece of tubing on the end of a rubber line .[ I use a small brass or alum.  tubing . Make sure the tube is long so that you can not accidently drop it in the pump.
 One can find this small tubing in any Hobby Shop in 1 foot lengths
 I have a glass jar that has 2 hoses coming out the top .. one goes to a vac pump and the other goes to the rubber siphon hose .. then you can see what is going on and the oil will not get to the vac source.. just make the holes in the top  a little smaller than the rubber hose and slip them through the holes with a little soap/lube and they will seal  themselves.. no need for fittings.[ same type of set-up one would make/use for brake bleeding]

 After refill , try car and watch the oil level.. if it comes back up within a couple of weeks , you have a bad sealing  pump.
.. but you may just have an accumulation over a large time span cuz nobody ever checked it..I have actually had guys come to me and said thy did not even know it was there and owned the car for over 10 years.

 
 

[A Dalton]

Rodd
 Did not bump your post.. we were typing at the same time .. and I am a 2 finger typerer..