Topic: BMC 1500 Injection Pump Pointer

antrobii    -- Jul-20-2019 @ 8:39 AM
  Hello Everybody.

I hope you are having a good summer Smile

I want to make sure that the position of the timing pointer on the block of our 1500 BMC is right.

I get the 22-degrees BTDC on number 1 compression stroke and the 5 o'clock position for the master spline on the pump drive.

But the manual says to 'set the MS67A universal timing gauge to 208 degrees'.

I don't have an MS67A gauge, I've printed up my own scale that fits over the pump studs.

Does anybody know if that is 208 degrees clockwise or counterclockwise, as viewed down the pump spindle toward the block?

And it is presumably measured from the master spline 5 o'clock position?

There is surprisingly little information about these engines on the 'net.

Thanks in advance!
Kind Regards,

BuffaloBill    -- Jul-21-2019 @ 11:07 AM
  Hi Terry. I'm not sure if this is any help for you but may give you the answers that you are looking for.

BMC 1500 Workshop Manual

The older I get...
The better I was....!!

BuffaloBill    -- Jul-28-2019 @ 11:29 AM
  So a week has gone by and no acknowledgement to my answer!
And people wonder we don't bother........

The older I get...
The better I was....!!

antrobii    -- Jul-28-2019 @ 4:48 PM
  Bill. I am an infrequent visitor. I am sorry if you are upset by my slow response. It certainly wasn't me ignoring your response as you imply.

Thanks, but have the manual, it doesn't precisely answer my question.

Looking at the engine again, it must be 208 degrees CCW from the 5 o'clock position.

That puts the pointer in advance of where it was before, which was producing clouds of white smoke.

I'll find out once the engine is back in and running.


steve    -- Jul-28-2019 @ 9:53 PM
  Hi there,
Maybe worth having a word with lord Paul ,or hopefully he may see this a post up , sure he had the same trouble with hes one , with white smoke on start up etc ,

steve and vicky
( apparently a moaner)

BuffaloBill    -- Jul-29-2019 @ 7:21 AM
  Apologies Terry but it happens so often these days.
Can you borrow a compression gauge? You could have a
leaking head gasket or,worse, a cracked head.
I would certainly check the timing first and then
do a compression test before going any further.
It sounds like water is getting into your fuel or
cylinder somehow, hence the comment above.
Good luck and do tell when you find the fault.

The older I get...
The better I was....!!

ncsl    -- Jul-29-2019 @ 7:32 AM
  I can not offer any tech. Advice other than on mine the smoke was due to a knackered timing chain and tensioner. I had it changed and all ok now.

I cruise on THE NORFOLK BROAD as I can not cruise on something that is NOT.

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antrobii    -- Jul-29-2019 @ 8:21 AM
  Thanks again for these responses.

I am certain that the white smoke is was unburnt fuel and not steam. I am convinced that the timing was quite a way out, 5-10 degrees retarded at the pump. The engine ran but was a very, very poor starter. The smoke didn't stop after warm up.

There is of course much discussion about smoking diesels on the internet. There are a number of variables that means that no one answer can be the right one for every given problem.

The engine is on an engine stand in my garage at the moment. I will indeed do a compression check before putting it back into the boat.

And thanks NCSL, I did replace the timing chain. I bought an aftermarket made-in-India tensioner too (they are the same as are fitted to MGBs) but after having read of problems of the bonded rubber face falling off decided to refit the old Renold one, which is still serviceable. Renold tensionsers seem to be hard to get hold of these days.  

There is now a marked difference in chain tension, which will indeed help.

I'm close to refitting the timing chain cover and sump which will mean it can go back into the boat Smile  I am terribly slow at this kind of stuff, I get distracted with other projects. But I will update this post with progress and certainly the results once the engine is running again.

For interest, I have attached a screenshot of the simple gauge that I drew up. It is not to scale in that image. I marked the 3,4, and 5 o'clock positions and that 208 degrees CCW from 5 o'clock.

Thanks again.

annville    -- Jul-29-2019 @ 2:20 PM
  Hi Terry place ring spanner on dog nut turn crank clockwise see/look which way pump spindle turns if clockwise turn pump anti clockwise to take up lash bad starting on BMC's is usually heater plugs if battery power ok and smoking is usually injectors they want cleaning/resetting this assumes compression is ok, timing doesn't move by itself chains don't stretch that much unless worn and touching timing cover leaving groves in the cover. John

antrobii    -- Aug-8-2019 @ 3:05 PM
  Thanks John.

Who knows, the timing could have been wrong forever Smile  it is worth checking while the engine is out.

I had replaced the injectors and glow plugs before removing the engine, which made no difference.

I know that wear and tolerances can alter the pump pointer position, but I'm not sure by how much. Surely the pointer will be reasonably close on all engines given that master-spline-at-5-o-clock setup.

I have attached an image that shows the position at which the pointer arrives using my DIY gauge - the red arrow - and my recollection of roughly where it was previously - the blue arrow.

Pump rotation is CCW, so the new setting advances pump timing by some considerable amount.

It would be interesting and helpful to know if pointers on other engines are anywhere near to my new position, which as you can see is a little in advance of the pump fixing stud.

All is not lost if its wrong: it will be easy enough to adjust once back in and running, unlike the setting of that 5-o-clock position which is not easily done with the engine in situ.


This message was edited by antrobii on Aug-8-19 @ 4:06 PM

Dilligaf    -- Aug-8-2019 @ 7:02 PM
  Different pumps on my old peugeots but they were cav and I set them to the info I had and they ran cr*p with lots of white smoke, then found out there was a number etched into a cap on the side that needed to be added to the book figures to get them right, each pump has a different number determined when the pump is built.
A tweek by hand while running found a sweet spot and the smoke cleared and ran much better.
A diesel fitter timed them the same as I did and made the same mistake till he consulted the cav manual in depth.
I think they were dpc pumps.

Formerly 'LeoMagill'

antrobii    -- Aug-9-2019 @ 9:51 AM
  That's interesting, Dave, thank you.

That is logical: in addition to the manufacture of the timing drive system, the manufacture of the pump is not an exact science to the nth degree of tolerance.

I was anticipating having to tweak the thing once up and running, but have been trying to make sure that I have the pointer in the right kind of area to begin with Smile

I'll be doing some more work on it tomorrow - replace the timing cover, sump and the bell-housing casting. It is then ready to go back into the boat.

I'll update with the results, but it is likely to be some time before I get it all fitted up and running again.


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