Md7a Fuel Injection Manual

[Coyote]

I am new to working on my md7a. Mine has the CAV injector system. I am having trouble keeping the system bled. Clearly, I have a leak somewhere, doubtless my own fault.

My suspects are:

1) One of the bleeder valves may be leaking.

2) The fuel filter gasket might be leaking.

Does anyone know where I can get more detail about this system? The manual I have gives me a picture about 40 pixels on a side and that doesn't help. I would love an explosion diagram, information on parts sources, or even better a real manual on the FI system.

[MMNETSEA]

From your post I take it that you have the workshop manual ? ( if not, I have the 44 page MD7A manual in pdf format, if you need)

For Info, the CAV pump is now the Lucas CAV.

From the brief description it looks like a slow leak somewhere. Can you see into the primary filter if so, can you see a small bubble trail when the engine is running ??

In the manual I have, para 75a 0n page 28 gives bleeding order. On page 33 there is whole section dealing with bleeding. Maybe the best bet is to replace all washers - 'O' rings, copper compression washers etc.. and the re-bleed the whole system.

Parts Link HERE

[Coyote]

Thank you for the reply and the link. Yes, I have the 44 page manual, but it is a little slim on the FI system.

Do you know a model number or more keywords I can search for on the Lucas CAV? This would help with ordering parts and with finding information.

My hope, and I know it may be futile, is for an explosion diagram of the system showing the parts in the bleeder valve and maybe give a hint on taking it apart and reassembling it without making a mess. Armed with this information I would probably just replace all the replaceable parts as you suggest and see where I get.

I do not have any clear filters or lines. Perhaps I should replace a piece of line with clear plastic for a while until I debug this.

Thanks again for taking the time to help.

Chuck

[harbin]

I purchased my Islander 30 with a Volvo MD7A engine last fall. The surveyor recommended I replace the fuel lines with qualified A1 hoses - which I did over the winter. I believe that was the begining of my problems. Now I have to vent the fuel filter (no pre-filter) every 1 to 6 hours of running time. I have replaced the filter and added a squeeze bulb to get things going each time. It's taking the fun out of sailing. I still have a few ideas but I'm about to turn it over to the mechanic.

[Coyote]

In case this is of use to anyone, I finally found the trouble. It was two things:

1) The gasket on the fuel pump cover was leaking.

2) The cartridge on the first fuel filter was leaking.

Of course parts are available for neither. I made a gasket for the fuel pump and got that under control. This was the main problem. Then I replaced the fuel filter with a newer model with twist on cartridges that are less likely to leak and easier to get parts for anyway.

She purrs like a kitten now.

[KnotAllThere]

I realize this thread is rather old now. I am having the same issue with the seal on the front of the fuel pump. How did you end up removing the cover? I have removed the 4 screws and the fittings that the high pressure fuel lines attach to but the cover only comes off the body about 3/16", not quite enough room to male a new gasket. The other issue I have is not being able to get the fuel to stop dripping. If you see this reply, any help would be greatly appreciated.

Thanks in advance.

[Brent Swain]

I once saw a bumper sticker, which said "Any parts found falling off my Volvo, are of the finest Swedish craftsmanship." Volvos should be scrapped , before they break you. You will end up scrapping them anyway. Best do it before they cost you a lot.