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Steviej

McCormick International B250 TDC

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G’day All,

Having trouble getting my engine to start and run well after putting new rings in it.

lots of white smoke, hard to start and runs rough.

If I put the front pulley on TDC does it automatically mean it’s on the “compression stroke”?

or does pass TDC a number of times before that?

cheers

steve

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Hi, could either be on compression or exhaust TDC, on a the B250 Diesel, you can remove the Glow plug for #1 cylinder and put your thumb over the Glow plug hole while rotating the engine and you will feel the compression on your thumb, another way is to remove the valve cover and watch when both valves are closed on cyl #1.

See this youtube: https://www.youtube.com/watch?v=O8H54pKeNEc

 

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G'day and Thank You Jim,

I'm now certain I have them set correctly. It is still very hard to start, runs rough and punches out lots of white smoke. It occasionally sounds like it fires up the exhaust. There is some black liquid, which i assume is un-burnt fuel coming out the exhaust. I can crack injector pipe 3 and 4 with out it changing note (defs fuel there though), however when I crack 1 or 2 if definitely runs worse. I've moved the injectors around and it doesn't make a difference so assume its not the issue. Its further back down the line.

I'm moving on to checking out the fuel injection system. I've emptied the fuel tank, flushed and refilled.

Next I will check the timing. Seems like a difficult operation but I need to find the issue soon, I've got plenty of work lined up for the old girl.

Cheers

Steve

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Might sound obvious but are the injector pipes in the correct order?  Probably difficult to get them wrong but I have seen it before.   Are all your valve clearances correct? 

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 G’day,

 Nothing is too obvious. But your right, they are difficult to get wrong without bending the pipes. That being said, I compared to a few pics and they are ok. 

Ive checked and rechecked the valves clearances ensuring I was at TDC on the compression stroke. So am very confident they are good.

Would be nice if it just worked tho, it’s getting frustrating.

Cheers

steve.

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Odd that two cylinders don’t have much effect if you loosen the injector pipes. 
Does it have an inline pump or rotary?  
if it’s an in-line I suppose it’s possible one or two of the bolts that operate the plungers (control rack ) have moved. But I would expect black smoke if two cylinders were getting excess fuel And not much smoke if they weren’t getting enough. You could try moving the timing a little either side of where you have it now. Also worth doing a compression test. Just to be sure everything in the cylinders is ok. 

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Thanks England806,

Yes, odd. I think that’s means that those 2 cylinders are not firing.the white smoke I took to indicate fuel that had not burnt.

It’s an in-line fuel injector. I’m not not sure exactly how to adjust the timing, but gather it may be a case of loosening the pump bolts and rotating it a few degrees?

Cheers

SteveiJ

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The white smoke is Un burned fuel.   Some of the pumps are slotted to allow a small amount of adjustment to timing. If not you will have to remove the cover plate in front of the pump. There is adjustment inside the timing cover. Although I’m not convinced timing is the problem if two cylinders are firing ok.   Was it running on four cylinders before you did the work on it?  If you have made no changes to the pump and timing then it sounds like a possible lack of compression in the non running cylinders. 

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I would check the compression on 3 and 4, and check for valves riding open

 

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G’day Folks,

Thanks all for the help. 

Compression over 300 on all cylinders. 

Checked timing by spill method. Found it was out by 14 degrees.

Adjusted to 20 BTDC and it started without any ether like a new one.

Ran with hardly a puff of smoke.

I’m very pleased and couldn’t have done it without this forum. 

Thanks again. 

Cheers

StevieJ

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