VP MD202B - No compression

[NormanB]

I will try and add some further information/clarity, to some of the points raised.



It is a semi-reconditioned engine, specific work detailed on the included cylinders honed, valves relapped etc, but I do not think the rings were replaced. Since fitting it has only been run for 30 mins. The main components should be OK, or at least were.
.

Just an observation.

I cannot imagine how any competent engine rebuilder would ever consider honing bores and then refitting the original piston rings. It is just so much work to strip an engine to risk taking such a shortcut and risk the need to do the job again very soon. If the person was prepared to do this maybe they used the old head gasket as well!!!!!

I would have serious reservations about the true state of this engine.

Sorry.

 

[pvb]

I cannot imagine how any competent engine rebuilder would ever consider honing bores and then refitting the original piston rings.

Yes, I noticed that too. Worrying.

 

[philwebb]

The guy who "reconditioned" this engine does not deserve to be called a mechanic. If you go to the trouble of honing the bores, the rings should be replaced as a matter of course. Most likely with slightly oversize new rings. The pistons should have been checked for wear at the same time. Anything else is a bodge. I would not trust any of the work that this man has carried out on this engine. I think what has been done should be checked by somebody reputable and qualified.
Like others I am still mystified as to why the engine won't run with a dose of easy start. This suggests absolutely zero compression close to TDC.

 

[mjf107]

Consider that the valve and injection timing is correct for a moment, personally have no strong feelings if this so.
The dismantling process could have caused a failing exhaust hose to delaminate resulting in a block exhaust system.
This in turn would prevent a fresh charge of air being drawn in for the next compression stroke resulting insufficient oxygen for ignition. Indeed if there was some over pressure left in the cylinder when the inlet valve begins to open it could escape via the air intake as smoke as observed. With extended cranking over fueling could result in the loss of compression by washing out the natural seal of oil/carbon around the piston cylinder interface, under these circumstances I would think even a reasonably good engine might show signs of crankcase compression. Might be an idea to check exhaust is clear before delving deeper

 

[RichardS]

I thought I was patiently explaining some of the history to Paul, turn my back for few minutes to feed the cat and come back to find Ricahrd and Drydog fighting in the middle of the floor.

For once, we agree. I didn't see it coming either ..... and I haven't even got a cat!

I responded to your "put-down", as you absolutely knew I would, but then DD posted and seemed very upset and agitated about my response to you so I assumed that there had been a misunderstanding which I tried to clarify and proffer my apologies for. Unfortunately the poor chap went into some kind of melt-down and came back with an incoherent rant. He finished by asking me to confirm that I had understood his rant, to which I politely answered "no" as it was complete gibberish. You then came along and DD lost interest in our exchange and I went off to the family birthday dinner (not mine thankfully!).

That really was a first for PBO I reckon but it livened up the thread as we wallow around pending definitve news from Gary.

Richard

 

[Heckler]

For once, we agree. I didn't see it coming either ..... and I haven't even got a cat!

I responded to your "put-down", as you absolutely knew I would, but then DD posted and seemed very upset and agitated about my response to you so I assumed that there had been a misunderstanding which I tried to clarify and proffer my apologies for. Unfortunately the poor chap went into some kind of melt-down and came back with an incoherent rant. He finished by asking me to confirm that I had understood his rant, to which I politely answered "no" as it was complete gibberish. You then came along and DD lost interest in our exchange and I went off to the family birthday dinner (not mine thankfully!).

That really was a first for PBO I reckon but it livened up the thread as we wallow around pending definitve news from Gary.

Richard

Just got me a second cup of tea
S
PS doesn't any one live near by? I offered to pop around till I realised it was a days drive away from here!

 

[RichardS]

Just got me a second cup of tea
S
PS doesn't any one live near by? I offered to pop around till I realised it was a days drive away from here!

I assume that Gary's boat is in Wells-next-the-Sea. I was visiting a place called Holt a few weeks ago which I think is quite close .... and it was a 5 hour drive from here although that was in a Series 3 Landrover .... so about 15 minutes in a normal car!

I'm out of ideas for Gary but I think that Vic still one idea left which he has not yet told us. I'll bet that he has it right and we'll all look like amateurs.

Richard

 

[VicS]

I assume that Gary's boat is in Wells-next-the-Sea. I was visiting a place called Holt a few weeks ago which I think is quite close .... and it was a 5 hour drive from here although that was in a Series 3 Landrover .... so about 15 minutes in a normal car!

I'm out of ideas for Gary but I think that Vic still one idea left which he has not yet told us. I'll bet that he has it right and we'll all look like amateurs.

Richard

I had a theory but discussed it with Stu by PM and dropped it Subsequent confirmation that the valve gear was apparently operating correctly ruled it out.

FWIW I was wondering if while working on the front plate Gary had displaced ( or even removed) the crankshaft gear and the the key, which appears to be a peg or dowel rather than a Woodruff key, had fallen out without him realising with the result that the crankshaft was now turning on its own .... but proved to be not so.

Still could speculate that the key is missing and that the crankshaft gear is not timed correctly on the shaft but very improbable I'd think. Although it would satisfy the "incorrectly timed" brigade

 

[lw395]

Just an observation.

I cannot imagine how any competent engine rebuilder would ever consider honing bores and then refitting the original piston rings. It is just so much work to strip an engine to risk taking such a shortcut and risk the need to do the job again very soon. If the person was prepared to do this maybe they used the old head gasket as well!!!!!

I would have serious reservations about the true state of this engine.

Sorry.

Perhaps the ring gaps were measured and found well within limits?
Maybe the head gasket has disintegrated, either through re-use or being a faulty part?

 

[ghostlymoron]

All very interesting but some irrelevant. Comments about the standard of work before he partially dismantled the engine can't be causing the current problem as the engine has run on up to now. The problem MUST be with something he has dismantled and not put back correctly.
Unfortunately, I've no idea what but I would be calling the cavalry at this stage or repeating what I had done.

 

[Heckler]

I assume that Gary's boat is in Wells-next-the-Sea. I was visiting a place called Holt a few weeks ago which I think is quite close .... and it was a 5 hour drive from here although that was in a Series 3 Landrover .... so about 15 minutes in a normal car!

I'm out of ideas for Gary but I think that Vic still one idea left which he has not yet told us. I'll bet that he has it right and we'll all look like amateurs.

Richard

http://www.google.co.uk/url?sa=t&so...ns.pdf&usg=AFQjCNHzwFSCJtqehCf_Y5vncrfZ1ugzLQ

Just been looking at the workshop manual and the advance/ retard, sorry , governor unit on the camshaft/inj pump drive gear. See 4-16. I did mention it in passing earlier, if Gary has disturbed this and not really assembled correctly then it could explain where damage to valves has come from.

 

[ghostlymoron]

BTW Stu, congratulations on your appointment to the experts panel.

 

[Heckler]

All very interesting but some irrelevant. Comments about the standard of work before he partially dismantled the engine can't be causing the current problem as the engine has run on up to now. The problem MUST be with something he has dismantled and not put back correctly.
Unfortunately, I've no idea what but I would be calling the cavalry at this stage or repeating what I had done.

BTW Stu, congratulations on your appointment to the experts panel.

Thanks! Got a lot to live up to!
Stu

 

[PaulRainbow]

All very interesting but some irrelevant. Comments about the standard of work before he partially dismantled the engine can't be causing the current problem as the engine has run on up to now. The problem MUST be with something he has dismantled and not put back correctly.
Unfortunately, I've no idea what but I would be calling the cavalry at this stage or repeating what I had done.

If he does that he'll still have the same problem

 

[NormanB]

All very interesting but some irrelevant. Comments about the standard of work before he partially dismantled the engine can't be causing the current problem as the engine has run on up to now. The problem MUST be with something he has dismantled and not put back correctly.
Unfortunately, I've no idea what but I would be calling the cavalry at this stage or repeating what I had done.

Without wishing to be the harbinger of doom I have seen many a fault finding 'expert' wrong footed by hanging on to that sort of assumption. I do not profess to know what the problem is, but a logical fault finding approach that does not assume anything is much more likely to derive success.

 

[ghostlymoron]

Without wishing to be the harbinger of doom I have seen many a fault finding 'expert' wrong footed by hanging on to that sort of assumption. I do not profess to know what the problem is, but a logical fault finding approach that does not assume anything is much more likely to derive success.

I'm not a fault finding expert but as it was working ok before dismantling to fix the oil leak the fault logically must have been introduced since that was done. I'm not jumping to conclusions and am not a diesel buff.

 

[ex-Gladys]

I'm not a fault finding expert but as it was working ok before dismantling to fix the oil leak the fault logically must have been introduced since that was done. I'm not jumping to conclusions and am not a diesel buff.

I have to agree with NormanB... This is the easy "assumption", I can't tell you how many times I've done that with motorcycles etc, you do have to completely rid your mind of assumptions and start as if you'd done nothing

 

[Heckler]

I'm not a fault finding expert but as it was working ok before dismantling to fix the oil leak the fault logically must have been introduced since that was done. I'm not jumping to conclusions and am not a diesel buff.

GM, you are correct. Given the info we have. I have spoken to Gary, he confirmed the engine was running ok, the only issue was the oil leak.
Stu

 

[ghostlymoron]

Thanks for your agreement, Stu. I've just read Gary's other thread which refers to six others starting with his unfortunate breaking of the pulley. As I said previously, it's time to call the cavalry - he's suffered enough. Pity he's on the other side of the country, you could have given him a hand.

 

[Heckler]

Thanks for your agreement, Stu. I've just read Gary's other thread which refers to six others starting with his unfortunate breaking of the pulley. As I said previously, it's time to call the cavalry - he's suffered enough. Pity he's on the other side of the country, you could have given him a hand.

I said that if he had been nearer I would have been happy to take a look, trouble is that he is half a days drive away.
Stu