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1977 MD11C - Trick to bleeding the engine after fuel filter change

cedmunds

Member
Hello all,
hoping to save myself from doing something stupid (if it ain't broke don't fix it) by posting here to see if any of you know some trick I don't to get my MD11C bled and restarted after changing out the fuel filter. The engine was not starting easily (lots of cranking even with the cold start button pushed down) so I decided to change out the fuel filter.
- Went to boat, got the engine started and ran for 20 min (easier to get it restarted after it is warm)
- shut engine down and changed the fuel filter (being sure to fill the fuel filter bowl before re-attaching to engine - I have old fuel filter bowl type with single bolt that holds bowl to lid with single bolt down the middle) Made sure fuel filter gasket was tucked into groove for it on fuel filter top (don't have a new gasket but old one looked ok)
- figured out the little hand primer pump lever was hitting engine mount so worked on it and finally got it to make full stroke and managed to get good fuel out of the fuel filter bleeder screw
- Tried to start the engine thinking I might get lucky and it would start and run
- It started then died as if it had used up the fuel in the bowl and was again fuel starved - could not get to injector bleeds fast enough to do anything while it was still running
- Got fuel filter bled again then tried to bleed at the injector pump but could not get any fuel to come out of that bleeder screw (manual says should not have to bleed at injector pump unless new engine or fuel run completely dry)
- tried to start engine again and it would not start - that is where I am stuck
- do I need to get fuel to come out of that bleeder screw on the injector pump and, if so is there a trick to it?
- I read an article about another MD engine (that I think was a single cyl MD5B) where it was stated you had to disconnect the high pressure side of the fuel injector and loosen the delivery valve holder. pressure connector but I don't want to do that unless it is really necessary
- anyone tell me what I am doing wrong?
stuck in the slip and FL - Carole
 
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I don't know your engine at all, so take all this with a 'grain of salt'. It is based on experience with a different pair of much newer Volvo's.
From what you have described I would suspect that the diaphragm in your lift (primer) pump might be holed. That is assuming of course that it is a diaphragm lift pump? That would explain pretty much everything that you have experienced including the initial hard starting problem. On our Volvo's we do the bleeding on the odd occasion it is required by cracking open the nut where the pipe goes into the injectors and then first pumping the lift pump, and secondly winding over the engine on the starter until we see fuel squirt. Tighten up the nuts and then start.
As I said, this is not based on knowledge of your engine, but hopefully may be of some help.
 
thanks aliboy for responding. I don't think that it is the little diaphragm feeder pump because it is is pretty new and it does pump fuel out through the fuel filter bleed screw. I did have the cover off of the diaphragm feeder pump to check the little filter screen inside it -that was ok. The fuel injection pump is another story though. For awhile I did have someone there to crank the engine while I cracked the injector nuts. During that process the rear injector seemed to get fuel spurts but not the front injector nut but that was before I went back to the beginning and started all over taking the fuel filter bowl off again bleeding the filter again etc. Now I get no fuel coming out injector nuts when engine is cranked and the stopping point seems to be the fuel injection pump...as if there is some sort of air lock or injection pump is not in the right position to allow fuel to flow out of the bleeder screw...thinking about that I'm going to try rotating the fly wheel and see if at some position it allows fuel to flow out of the bleeder screw on that by pumping the feeder pump. Other possibility I am thinking of is that something I did caused the fuel system to pull in air such as at the feed pump or at the fuel filter gasket. Schematic of fuel system is here:
http://www.marinepartseurope.com/PentaPictures500/6220.jpg
 
Update - back to the boat today and again tried to bleed the engine- this time could not get any fuel at the fuel filter bleeder screw either by pumping on the priming feed pump or turning the engine over. Questions: Does turning the engine over (cranking) cause the feeder pump to pump to fill the fuel filter bowl? If so how long can I safely turn over the engine to try to prime the fuel filter? I only cranked a few seconds (10) at a time trying to start/prime? Can I crank it over via starter & battery safely for a longer period of time than that?
 
Guessing a bit again, but if you have air in the injector pump it may not pump fuel until you have re-primed it with the lift pump. If you can't get fuel flowing with the lift pump you might turn the engine forever with no result.
 
thanks aliboy, back to the boat tomorrow to try again. Got a new gasket for fuel filter bowl so will drop the filter, replace gasket refit and try feed pump again. If no luck then drop fuel feed pump put older but I think still working one back on (replace it because it leaked a little oil from under pump lever) and try again. If that does not work then I guess I will have to start back at the tank (I hate to undo that connection) maybe try to hook up a manual fuel pump bulb to see if I can pump out of the tank with that to make sure the fuel pick up there is not clogged or something. The whole thing is weird...like I said I ran the engine 20 min prior to changing out the fuel filter. I did try to hook up a mighty mite (used to help bleed brake lines on cars) to the bleeder screw hole on the filter today and suck fuel up and out of that hole and did not get anything out of it with 15lb pressure...that makes no sense to me either. Still trying...mobile mechanic want $85 per hour including travel time and I am afraid even if I paid that he would not know that old engine and might tear apart stuff that is not replaceable..parts for this engine MD11C are VERY hard to get. Made my own replacement metric fuel filter bleeder screw today for fuel filter as old one the head of it was messed up. Got an 8m x 1.0 and made a bleeder slot with dremel. Read that on this or blog. Thanks for following my troubles and trying to help. Oh yeah I also took off top of water injection into exhaust elbow today and made sure there wasn't a lot of back pressure there (ran some vinegar down and out).
 
If you can't get fuel squirting by turning over the engine with the injector nuts loose then it is almost certainly in the pump/primer/filter setup somewhere.
 
G'day Carole,
I have not read all the posts so a lot of this has possibley been suggested my opologies to those people. Start the bleeding process at the tank and work towards the engine making sure ALL air has been cleared from water traps ete,once at motor undo engine filter bleed then use lift pump to expell fuel clear of ALL air bubbles no matter how small, if after much pumping fuel is not seen at filter this means engine has stopped with the cam pecker at full travel leaving the diaphram depressed, rotate engine 360 degs by hand and try again camshaft and fuel pump work at 1/2 engine speed, once clear flow move onto hp fuel pump and repeat then undo injector leads at injector end, decompress motor make sure stop lever is set to RUN position apply full thottle then crank engine over untill fuel shows at pipe end, firmly tighten fittings engine should now start. If you are located in a area moving into winter with dropping temps this could be the cause of your reluctant to start issue, how long since valve clearances have been done?
 
Thanks shakey. I did not know about the fuel pump works at 1/2 speed part. I did know about rotating the fly wheel and rotated it a little at a time yesterday trying to find where the little feed pump lever felt more firm when pumped rather than like it was not trying. Part of what is making this difficult is that the engine mount interferes with free movement i.e. full stroke of the feed pump lever by hand not to mention how hard it is to get to- have to reach in blind from front right side of engine to do it. That raises the question - does operating the feed pump by hand operate it at more of its full pumping capacity than when turning the engine over with the starter? When I had someone turn over the engine with starter I felt no movement of the manual operation lever with my finger on it. That implies that the pump, when worked manually is independent from when engine cam works it? I guess I need more schooling on the theory of operation of such things but no book seems to go to that depth of information. You guys have it all over us girls in that respect, you all seem to be more natural mechanics....I just seem to wind up in "analysis paralysis". I do know one thing....If I have to keep working this little feed pump with my right hand/arm, I am going to have to find a certain piece of wearing apparel that comes in two different size cups!:) Valve clearances have not been adjusted for a long time but engine ran fine just before changing fuel filter, was just hard starting which I attributed to a fuel issue. Since I only have weekends, I will be back up at the boat trying again today.
 
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Oh...wanted to add that the fuel tank on my boat is lower than the fuel feed pump and filter....and I did not shut off the valve at the tank prior to changing the fuel filter. This morning read that maybe pressurizing the tank could force fuel back up the line?
 
G'day,
Most small engine lift pumps start struggle with lifts of over 4'. You may want to look at fitting a outboard type priming bowl in the circuit close to the lift pump or a electric pump capable of lifting, carefull as alot of inline electric pumps need a flooded head.There is a good book avaliable that covers pretty much anything you should need, author Nigel Galder can not think of the name Google will bring it up. Pressurizing the tank will help the pump do its job, don't forget to block off the vent line. You are right the cam side works independant of the lever. Sorry, cannot help with your other problem suggest a pillow across front of engine preferable in green tones so as not to clash with VP green.
 
Whahoo! Got it!! Pressurized the tank and got fuel out of fuel filter bleeder (that was the good news) bad news was that the gasket was leaking around where feed pump top and bottom fit together with not much pressure on it. 3 hours later after removing fuel filter bowl (for the third time) to get at the feed pump, removing feed pump (in a rotten place to get to) and tightening all the screws around the feed pump gasket the feeder pump primed the fuel filter and injector pump and turning it over the engine and cracking at injectors, it started! Ran it about 20 minutes under load in the slip and it seemed fine, no fuel leaks etc. I think the feed pump was sucking a small amount of air whole time but no leak to be seen until under a little pressure. Blondes do have more fun. Vacation here I come!!!NightWatchAtAnchor3.jpg:rolleyes: Thanks to all of you who responded.
 
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Great news. After all that work it came right back to the very first thing. Lift pumps are nearly always my number one suspect on older Volvos with fuel issues. Those and the Racors etc seem to be the weak link in the fuel chain. Now go and enjoy it!
 
Thank Aliboy...I will enjoy it but also still have a lot of stuff on my TTD list. Want to take off exhaust manifold & clean it and cooling ports; take out exhaust elbow and check its condition (was weeping a little and I put JB weld on outside of it. I have a small oil leak I need to find and try to fix. I think it is either where the engine and xmission join or drain plug under MSB xmission. I have a dish pan under engine to catch anything that leaks but have to keep a close eye on oil levels. I have been through the "clear out the cooling system" before so that should be something I can get through pretty well. Want to change out the raw water pump (just on general principle) so I may be back for more help later. One thing I want to ask if someone knows is what could I coat the inside of the water injected exhaust elbow to seal and slow down the corrosion process? I have thougt of high temp epoxy, ceramic or??? Those elbows are nearly impossible to find and VERY high price if you can find one. Again thanks for the help. Here is pic of my volvo- not the classic volvo green...I like this color better anyway. You can see the "getting at stuff" problem. I think I will make my future thread posts "volvo for dummies questions"
volvo2.JPG
 
You could try the epoxy in the pitting in the elbow. Don't know how you could get a ceramic coating done. Another thought would be a machine shop that has a 'metal sprayer'. Never heard of one used for an exhaust elbow, but may be possible. Other option is to find a good welder and get it welded. Last thought is make an adapter plate so a more common elbow can be used. Never tried this, but can think how it would probably work OK on most engines I have worked on. Blue Volvo? Did the last owner get sick of the green because it reminded him of all the $ bills he was tearing up, or were they trying to disguise the fact that it was a 'green grenade'??
 
Alliboy, well the "blue" this was me doing de-rusting (wire brushing) and repainting things with high temp engine paint of another color...guess I got carried away with it. On the exhaust elbow I think you are on target with an adaptor of some sort. I was thinking take it to a welding shop, have the top cut off (piece that is bolded onto the engine including the water injection point) then have the shop weld a threaded piece onto the cut off part so pipe elbow say 45 degree and straighter down piece can be refitted whenever needed. However I am not sure how plumbing store parts would stand up to the exhaust heat and how threaded joints would hold up to the vibration factor. I probably will not do that unless the current one looks really bad or blows out. JB weld seems to be working for now and I can blow through the connected hose (water injection) and push air all the way through to the outside. You are right about the money pit thing concerning this engine....but I love my little Volvo cause it is straight forward to understand (pretty much) and Nigel Calders book (early edition) shows that engine in a lot of its content. Also cost of a new engine plus installation is cost prohibitive at this point. I just gotta keep my eye out and track down spares as they become available. I have been trying to watch for a used "take out" MD11C on craigs list or some place that I can afford to buy for spares. Xmission (MSB) and exhaust manifold alone are gold. So far I don't like the idea of replacing that engine with a cheap aluminum block Yanmar either. Seems like 1st overheat incident might be the end of it. This Volvo has lasted 30yrs and still runs well....anyone got a Yanmar that has done that? I don't know what other diesel will fit in that space...I've heard maybe Beta?
 
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