posted May 05, 2004 08:37               

regards

posted May 05, 2004 13:01               

quote:

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Originally posted by patsy1:
I have just got my starter motor for my super dexta rebuilt it is turning the engine fine but it will not start. The tractor starts fine by towing.Would it make any differnce if i used a standerd dexta starter. Can anybody help me please

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posted May 05, 2004 19:51               

In the past, the tap/pump system has been unobtainable so a later type of heater plug incorporating a valve could be adapted. This requires a small resevoir of diesel to be held for when the valve opens. This is done by a pipe "T" ed to the fuel return pipe from the injectors to tank. (The fuel pipe should not be fitted as a straight pipe from injectors to manifold.) About three spiral turns in this pipe will hold enough fuel to fire the engine.

If you are fitting a new pump system, (these are now available here in England for those who would be able to take out a second mortgage) then the tap is essential to stop diesel being drawn into the intake manifold. If you fit the latest type of heater plug with a valve the tap is not needed.

If the engine starts with a tow, your only problem is either the heater as above or possibly a lazy starter due to faulty windings, battery or battery leads. If it needed bleeding or any other problem it would not start and run after a tow.

It might be that the engine is badly worn and has been started on ether. If this is the problem you will see lots of smoke from the engine breather. This would require a total engine rebuild which is not too expensive if you can do it yourself.

regards

posted May 06, 2004 01:08               

On your blue girl the speed that the piston travels is creating more pressure in the cylinder chamber than your starter is. Therefore the rate of decay (or leakage) is a factor affecting the maximum pressure achieved between the two methods. But pulling the tractor you can get enough pressure to ignite the fuel, by using the starter you can’t. That’s because you can get the engine to spin faster by pulling it.

The reason I asked you if there is smoke coming out of the breather tube, which would be indicative of blow by. Also if you are using a large amount of oil that is another indication of wear

Of course, if you really want to be sure you will need to take pressure readings on all the cylinders. Black smoke is an indication of an incomplete fuel burn. White smoke is a no burn, blue smoke an indication of oil.

posted May 06, 2004 10:33               

We are in early spring here and the weather is still cold so our old girls still need a bit of help.

Patsy says there is no smoke from the breather so the engine sounds in fair condition.

You are right about the speed of the pistons, that gives enough pressure, with the tow, to fire her up without the heater. If the heater is not working people start using that horrible ether which then leads to the wear and major problems. But the starter will have a hard job to replicate the tow conditions. I have had lazy starters and this is an area for investigation along with the battery and leads.

Patsy does not say how good the service job was on the starter and whether all the windings etc were checked. I had my Nuffy starter checked and serviced by Lucas and it still did not perform although it was supposed to be totaly reconditioned. A reconditioned unit from the local dealer cured all my problems.

Patsy, the feed from the filter will be under pressure and this can lead to too much fuel being forced through into the inlet manifold which could cause problems. The flow from the return is not under quite so much pressure so is ideal.

regards

Brian

PS.
I see you cleaned the air cleaner in petrol. If you do this you may find that you are asking all your questions direct to Henry Ford!! Do not use petrol in aircleaners, the petrol residues and vapours can cause an explosion in a diesel engine or when you use the heater.