Van won’t rev!!!

[kindasquirrelly]

Hello,
I recently took the head off my D24 (non turbo).
That went Ok.
Following the rebuild it wouldn’t run and the pump was not injecting.
I have changed it for a secondhand pump that starts well and ticks over smoothly.
However when I try to accelerate it struggles up perhaps another 500 rpm but that is all.
There are no bubbles in the fuel lines and I am on my second new filter.
Has anyone had a similar problem?
Any ideas as to what is the fault?
Thank you in anticipation.

[ngoma]

Welcome! We will try to help you but need more extensive detailed descriptions.

1. What is the history of the replacement IP?

2. You mention new filter. Fuel filter? Possibility the small inner seal is doubled up?

[kindasquirrelly]

Hello,
Thank you for your response.
The vehicle is a 1995 LT35
The pump was from a Volvo 740 but had been taken off the car by the breaker, it was quite dirty. I took the lid of and washed it out internally as best I could. I bench tested it using a reversed drill on the mainshaft nut and it appeared to squirt well at various ‘throttle’ settings.
The original pump had mysteriously stopped drawing fuel via the low pressure side of the pump. I could make it work using an electric inline pump but not satisfactorily.
Before I got to blaming the pump, I changed the pick up unit in the fuel tank. The flow and return pipes front to rear.
I removed the water trap filter and as it was drawing air in on the return side I swopped the fuel filter for a Ford one that just has an in and an out, the excess fuel now returns to the tank directly. There are now no visible air bubbles in the clear line to the inlet banjo.
As part of finding the route of this problem,
I bypassed the fuel filter, no improvement.
Replaced the return Banjo bolt with a new one.
Did the cam and pump timing again to be sure.
I have the locking plate for the cam and the peg for the pump sprocket but I have not yet used a dial gauge in the pump as I do not have the adaptor.
Sorry for all this detail but I have exhausted my knowledge and skills over the last six weeks.
Thank you
Michael

[ngoma]

Originally Posted by kindasquirrelly

I took the lid of and washed it out internally as best I could.

This might be a factor. The "throttle" lever is toothed, sitting on a splined shaft coming out of that top cover. Did you matchmark the lever to the shaft before disassembly? If not, there's a good possibility that you reassembled it one or more teeth off, enough to cause the very symptom (inability to rev) you describe.

In addition, the internal spring cage mechanism that links the throttle shaft to the IP internals is very difficult to get connected properly when reassembling the top cover.

Originally Posted by kindasquirrelly

Did the cam and pump timing again to be sure.
I have the locking plate for the cam and the peg for the pump sprocket but I have not yet used a dial gauge in the pump as I do not have the adaptor.

Then you really did not do the IP timing?

Originally Posted by kindasquirrelly

Sorry for all this detail but I have exhausted my knowledge and skills over the last six weeks.

no problem there, the more details the better for getting faster help.

[kindasquirrelly]

Hello,
I was concerned about being out on the throttle lever alignment so I took it off and substituted it for mole grips! It didn’t make any difference.
I took the cover off last week to check the bob weights moved and that the sleeve was sliding on the injector shaft, it was.
I took the control spindle out of the cover during dismantling and reassembled it the same way to be sure the spring didn’t come off

Do I need to set it up with a dial gauge? I was previously under the impression this was just fine tuning.
Thanks for the replies
Michael

[ngoma]

Originally Posted by kindasquirrelly

Do I need to set it up with a dial gauge? I was previously under the impression this was just fine tuning.

Yes very much so. You will see that just a tiny sliver of movement has an effect on the timing.

BTW the preferred method doesn't use that locking peg or twisting the IP about on its bracketry. Instead you loosen the rear cam sprocket and rotate it slightly about the end of the camshaft to get the desired timing value.

Here is the IP timing sticky (start at post #2)

Useful (I consider them necessary) tools for this procedure:

Top two in this photo, the offset wrench for the camshaft sprocket bolt, and the sprocket holder


offset wrench for the camshaft sprocket bolt


sprocket holder

sprocket holder detail (P/N)

[kindasquirrelly]

Thank you very much for all that detail. I shall remove the kindling I prepared under the van!
As I have the morning to myself and it is lashing down outside I shall borrow a dial gauge and set it up as described. I have a VE pump and Volvo manuals to assist ( to help get the fire going)😆
Michael

[kindasquirrelly]

Hello,
I checked the injection pump timing, when it showed 0.97mm lift it was three teeth out on the flywheel gear. I reset the timing by loosening of the cam rear sprocket as advised. She ticks over a little more smoothly and a little less smoke but still no revs increase.
I checked it three times to be sure.
I intend to put an electric pump in prior to the banjo on the inlet side to see if it is the primary pump is performing badly.
Any advice welcome.
Regards
Michael

[ngoma]

Originally Posted by kindasquirrelly

...it was three teeth out on the flywheel gear.

That's quite a bit, actually. IP throttle shaft back to factory original position?

Originally Posted by kindasquirrelly

...a little less smoke but still no revs increase.

Now let's see what the smoke can tell us. What color, how much, when?

Originally Posted by kindasquirrelly

I intend to put an electric pump in prior to the banjo on the inlet side to see if it is the primary pump is performing badly.

Make sure it's a low pressure pump. More than 3-5 PSI can start blowing the seals out of the IP. Why not put it before the fuel filter, so as to protect the IP from any fuel pump-introduced debris?