Pagoda SL Group
W113 Pagoda SL Group => Drive train, fuel, suspension, steering & brakes => Topic started by: paul_GB on January 31, 2013, 17:58:53
-
Any thoughts are appreciated..
My early 230sl pagoda has a rebuilt 230SL head on a rebuilt 250SE block. It has always run v rich on idle and I am suspiscious of the FIP that is fitted (after doing the split fuel/air test).
Unfortunately the FIP Pt No plates have been sandblasted at some time and not readable. From images Ive seen it looks like a 250 unit but I cant be sure. I might try uploading some pics for comment.
Currently I have an option to buy another used unit (# PES6KL70A120 R18, 0408026011, EP/RLA 1/11R) which from the Tech Man pages apears to be a 250SE unit.
My dilema is really.. given the head/block combo I have, is a 250SE FIP best suited.. or should I save my money and go source a 230 or 250 SL FIP instead?
Thanks for any help..
Paul
PS. does anyone know what the significanec of the 'A' or 'B' in the FIP Pt No refers to.. i.e. PES6KL70A120 R18 vs PES6KL70B120 R18 ? Ive seen both types for sale.
-
Adjust the idle mixture using the thumb screw adjustment on the back of the pump (with engine not running). This will lean up the mixture at idle and low rpms. Re-check with the split linkage test after running a bit.
-
Thanks Joe..
I have already adjusted the notched screw on the bottom of the pump to the leanest setting .. also I removed a shim from under the WRD. Neither seem to have made much difference to the iddle running. Hence my suspicions re the 250SE FIP compatibility. Not sure what to do next other than invest in another FIP to replace mine.
Cheers
-
Rather than removing shims from the WRD I think you want to do so from the Barometric Compensator; that is what leans out the mixture across the range.
-
Cees is correct. The oval WRD shims should only effect the cold mixture. The Barometric compensator effects both cold and warm mixtures across the range. It is very sensitive and a .005" shim will make a noticeable difference. To lean with WRD you remove shims and I believe it is the opposite with the BC. Someone might correct me if I am wrong.
-
Yes, add shims to the barometric compensator to make the mixture a bit more rich. I never worry too much about the warm up regulator as it's only functional for a short period during warm up. If it's so rich it fouls out spark plugs, then there's a problem. Focusing on 4% at idle might be more bother than it's worth. As long as the engine starts and runs properly until warmed, it's closer than you might think.
-
Make sure that your injection pump filter is not clogged. This will cause a very rich running situation while warming up. Yes, remove shims under the baro. to lean all speed ranges. Then do a split linkage test. You may have to use the thumbscrew to richen the idle mixture up a bit after the shim removal.
-
(What is the split linkage test? Just curious.)
-
With the mechanical fuel injection fitted to these cars, it is very useful to know if any problem you have is fuel related. By disconnecting the control rod that goes to the fuel injection pump you can isolate the air controls from the fuel controls, thus being able to aggressively alter one or the other by moving their respective controls independently. You will know of course, that correct engine running is dependant on correct fuel mixture and by separating the linkage and only controlling one or the other you are able to determine if any problem you are having is caused by an incorrect fuel/ air mixture.
-
FYI, you can temporarily turn the Barometric Compensator (BC) into a giant mixture control knob. This can be very useful for quick experimenting. First, mark the outside of the BC so you have a reference point. You can use a marker, or if you don't want to deface it, put a piece of tape on it and mark the tape. The mark will let you carefully count turns as you screw it in and out. Note the mark's initial position, then remove BC carefully counting how many turns until is comes free. Remove and set the shims aside.
Now, screw the BC back in without the shims, carefully counting turns until it's back to it's original position. Take a short stub of hose, say 2" long and 3/4" to 1" diameter, and wedge it between the BC body and the Warm Running Device (WRD). The purpose of the hose is just to provide a little friction so the BC won't rotate on it's own.
Start up the engine, and you can now screw the BC in and out to adjust the mixture. Once you have figured out it's best position, note it based on the mark that you made. Now remove the BC again, carefully counting turns. Add or remove shims such that when reinstalled with the shims, the BC tightens up at the correct position.
This is much faster than constantly disassembling and reassembling the BC with different shims, and trying to remember whether it runs better or worse than before.
-
I had a barometric comensator unscrew and almost fall off. :o The engine ran so rich that the plugs were fouled out so I had to get a flat bed to haul it home. After adding a small shim by mixing and matching different combinations, I was able to get it just right. It took a couple of days of driving before everything settled into a dependable running pattern so don't assume you have it right the first try.