Help bleeding MD5A

[Ship's Cat 73]

Since we got the boat (Leisure 23) last July that Volvo has always started 1st or 2nd turn until last weekend. It reluctantly started, ran for about a minute then cut out and wouldn't restart.
We're hoping it just needs bled (and both of us aren't very conversant with marine diesel engines) and to do so will require the entire companionway removed. So before we do that we'd like to know what to be looking for as there's virtually nothing but the front of the engine visible right now.
I've inserted a couple of photos of an MD5A -- NOT ours, but photos seen on the internet -- we just hope ours looks the same when revealed.
So, can anyone point out in these photos what we should be looking at?
Thanks in advance.

 

[ean_p]

Bleeding The Fuel System, Electrical System - Volvo MD5A Workshop Manual [Page 28]

many other such sources on line for reference......

 

[ChromeDome]

See the instruction book
http://www.varen4u.nl/pdfs/volvo/Volvo_MD5A_manual.pdf
pg. 19

 

[coopec]

There are a lot of YouTube videos on the subject. The same bleeding procedure is used a on any make of diesel motor.

 

[Ship's Cat 73]

Thanks ean_p, ChromeDome and coopec for your suggestions.

I should have said that I had done an internet search previously but must say that in any photos or drawings of the MD5A that I found, I found it almost impossible to see and identify any small items that we should be looking for.

Have been at the boat today and was unable to find any kind of priming lever in all the places that there might have been such an animal.
We loosened the arrowed and circled slotted screw in the photo and continued to turn the engine on the starter until the diesel ran with no air in it.
After re-tightening that screw the engine started and ran "just like we've always known it."

Prior to last weekend it had been 3 weeks since it had been started but NOTHING had been done to ANY part of the fuel system in that time to have allowed air into the system. (There is around at least 8 or 9 litres in the tank.) Mysterious

 

[ean_p]

Good news SC.
For reference is not the little lever ( yellow circle) not the pump lever mentioned in the bleeding instructions? I'm not familiar with your engine but from your photo's it certainly looks the part.

 

[oldharry]

If you havent touched the fuel system and there is plenty of fuel in the tank, then bleeding it wont help. You have a fuel blockage, most likely in the filter. Take it off, and check that fuel is flowing freely from the tank. Fit a new filter and bleed the system and it should start. There is a slight possibility that the lift pump diaphragm has failed. This is unusual, but is the next place to look if it still will not run. The rubber diaphragm may look OK, but replace it anyway if you have dsmantled the pump, as it only takes a pinhole leak to destroy suction.

You must make sure there is absolutely no air in the system, and that all the joints you have opened are fully air/fuel tight. Even tiny air bubbles will stop the engine.

If none of this works, you need a mechanic, but over 95% of sudden engine stoppages are fuel supply related. Check what is in the filter bowl. It may give a clue as to what is wrong: you may find a black sticky goo has blocked the filter. If so its diesel bug. If there is only a little, you can buy cleaners to add to your fuel to break it up, but otherwise the tank will need cleaning to get rid of it.

Good luck

 

[scottie]

If you are turning over a non starting engine the disconnecting the water to stop filling exhaust and getter water in block is advised

it is known for the engine to stop with the cam Jo on the lift pump sorted by turning engine over

 

[KAM]

I had an Md5 for 25 years. The easy way to test is just disconnect the fuel pipe on the injector and either waggle the lever on the fuel pump or turn the engine over on the starter and see if fuel spurts out. The bleeding instructions in the manual are clear. The weakness I found was there's an area on the cylinder head gasket that is very narrow and prone to failure which can cause a cooling water leak into the cylinder. Mine failed a couple of times.

 

[Rappey]

Venting is as follows:
1. Open the vent screw on the fuel filter.
2. Pump forward the fuel with the help of the hand primer until fuel free from air bubbles
flows out. Close the vent screw. If the pumping effect is poor, turn over the engine a
bit so that the pump drive cam alters its position.
3. If the fuel injection pump has been removed, or when starting an entirely new engine
for the first time, the fuel injection pump must be vent. To do this open the vent
screw on the pump. Pump with the hand primer until fuel free from air comes out.
Slacken the injector delivery pipe nut and turn over the engine by means of the
starter motor until fuel comes from the delivery pipe. Tighten up the delivery pipe nut
and start the engine.