volvo md5 starting problems

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nickfabbri

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i wonder if anyone can help me with this. I am totally new to boating and so know very very little. I have purchased a 1980 Jaguar 25 with in inboard volvo penta md5b ( ithink ) engine. The problem i have is that it is a bugger to start. It turns over for ages and seems to start after about ten minutes of trying. I had the engine surveyes before i bought the boat and it said that everything was in order. The starting routine i have is that i pull the choke out , turn the ignition to 12 0'clock for about half a minute and then try to start her. I dont think the engine has glow plugs so there is no cold start facility. Eventually she does start but i can find no constant that gives me a regular start up routine. It has been relatively cold recently ( around 9 degrees c ) . Any help gratefully received
 
I have an MD5a, so not much different I guess. My starting routine is VERY little choke (or none at all on the first attempt) and about quarter throttle with the drive disengaged. I get a clean start by turning the key past upright after a few (5) seconds, perhaps giving the throttle a slight 'blip'. I use a larger amount of choke only if really cold. All of this assuming you've checked the fuel line, filters etc.

Whether this is 'by the book' or just works well for me I don't know, I'm sure others will have an opinion!!

Hope this helps!!
 
[ QUOTE ]
i pull the choke out

[/ QUOTE ] Diesel engines don't have chokes! but maybe that is its cold start device

You will be able to see glowplugs screwed in near the injectors, if they are there, with heavy wiring to them (the injectors have pipes connected)

If you dont think there are glow plugs whats the point of the half minute wait?

Make sure the stop control is pushed in fully. Some Volvo injection pumps have a cold starting button on them but I dont know about the one on the MD5, usually difficult to find even when you know it is there! Crank at a faily wide throttle opening.

you will be able to down load an operators manual from this site

And maybe a workshop manual from HERE

Are you sure it is an MD5? the site for the operators manual illustrates the plate on which you should find the model number etc
 
Passing point, on my MD6a, the cold start is activated when you pull the stop knob to stop the engine, come it's a Vovo. Alters the injector pump settings, once engine starts it drops out.
Was this fitted to the MD5b ?

Brian
 
Normally the MD5a/b is very easy to start. Fully agree that the "stopping pull handle" should be completely pushed in. Verify on the engine itself that the working end is indeed at its end of travel! At normal temperatures, it should start with the throttle lever in neutral. In cold weather, quarter throttle helps.
If this fails: - either air in the fuel lines > loosen one injector nut a bit and push the fuel pump a few times till fuel squirts out. Fasten the nut again (not too tight). then same on the other injector.
> If this fails too, there might be carbon buildup around the injectors.

Cheers!
 
Thanks for all the advice. I've checked and it is a MD5B not an A.So i'm not sure if the same applies re the cold start
 
According to the man i bought the boat from ( who seems very trustworthy ) he rebuilt the injector before selling the boat on, so I'm assuming that it cant be carbon build up. I will try to bleed the fuel though, but should this need to be done before any start up ?
 
Some of the MD engines had a cold start knob fitted which looks like a choke however this is a diesel engine so apart from the button being the same shape the similarity ends.

To get the cold start to work you have to set the fuel lever to at least half throttle and then pull the cold start knob to the limit of its travel. You will see that this action depresses a button on the engine.

This engages cold start by allowing the fuel racks extra movement. the knob can be returned home once the cold start is set.

There is no partial with this knob. It is all or nothing and if the cold start doesn t engage then advance the fuel lever further and try again.

Do not be tempted to use easy start on cold mornings. If you have to then squirt some oil into the inlet manifold and wind the engine over decompressed before starting. You will kill your batteries before summer comes if you take 10 minutes to start /forums/images/graemlins/smile.gif

John
 
thalassa,[ QUOTE ]
then same on the other injector.

[/ QUOTE ] In fact it is a single cylinder engine!

Bilgediver,[ QUOTE ]
You will see that this action depresses a button on the engine.

[/ QUOTE ] That is what it is like on the MD11 and similar but I cannot see a button on the diagram of the injector pump I have looked at.

Nickfabbri,
Download the operators manual from my earlier link. that will clear up any confusion about the correct starting procedure. I am sure you will find that that the cold start control should be pulled out fully and that some partial throttle setting will be recommended. Also that there will be no requirement to turn the key to any intermediate position and wait because there is no glow plug
 
I am assuming therefore that would explain a certain biting point when the throtle gets to about 40 percent forward, or would that just be coincidence?
 
The throttle action on the power should be evenly progressive. Is the clutch a bit late engaging fully?
 
i have also now heard that starting problems can be due to either compression failure or faulty glow plugs. could this be the case with the md5, and if so how would i know?
 
please excuse me if i sound really stupid about this ,but does an md5b definately not have glow plugs? Some people think it does yet i cannot find anything in any manual that suggests them.
 
I am not going to down load it for myself but is there not a wiring diagram in the operators manual? That would show the glow plug (singular because it is a single cylinder engine.....correct?) if there was one.

Even if there is no wiring diagram in the operators manual the workshop manual will certainly have one. I am also sure that a glow plug would be mentioned else where in the manual if there was one.

I have already given you the links for both manuals.

The parts diagram that I have looked at does not show a glow plug!
 
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