Hard Start When Hot After Full Injection Pump Rebuild

[SiberianPatrol]

Ok here's the story. I took my 99 GU RD28Ti into a highly rated diesel shop because I was having trouble starting the engine after it was hot.After running diagnostics, they said my injector pump wasn't pumping at a high enough pressure and would require a rebuild. I was kind of expecting that, so I had them go ahead with a full rebuild. Fast-forward 2 weeks and they have completed a full rebuild of the injectors and injector pump - everything that could possibly be worn has been replaced with new and refitted.

They have installed the pump and hooked everything back up and, you guessed it - still having hard start problems. They have pulled the pump and tested it on the stand 2-3 times already now, each time replacing a few bits. When I talked to them today, they said the pump is now working perfectly when it's on the stand, but when the engine gets up to temp, it struggles to start.

I have a feeling this is the first Patrol these guys have worked on, as they are not super common around here (maybe 10 or so GUs around the city).

Can anyone give me any suggestions for things to tell them to look for as they try to sort out this hot start issue? Anyone have any experience with the RD28Ti hot start issues?

I'm really ready to get it back as it's already been 2+ weeks on what should have been a simple pump rebuild. For those wondering the service center is an official Bosch and Denso diesel service and they specialize in fuel systems.

[threedogs]

Could it be a relay failing when its warm, try swapping the ECU with the air con relay.
disconnect the battery whilst you do it to.
Have you thought about fitting a lift pump??

[SiberianPatrol]

Could it be a relay failing when its warm, try swapping the ECU with the air con relay.
disconnect the battery whilst you do it to.
Have you thought about fitting a lift pump??

I'll try the relay swap. It's actually still at the shop as their reputation is on the line and they want to solve the problem. What would a lift pump do and how would that help? Are you talking about a secondary pump closer to the fuel tank to assist the main pump?

[SiberianPatrol]

Does anyone on here still source the modified advance plate for the injector pump? All the threads I've read about it are 3-4 years old. Would be interested to get one and see if that helps.

[happygu]

You normally only need one when the pump is worn a bit .... not when then are just reconditioned.......


Is it cranking at normal speed, but not firing up, or is it slow cranking when it gets hot?

[SiberianPatrol]

You normally only need one when the pump is worn a bit .... not when then are just reconditioned.......


Is it cranking at normal speed, but not firing up, or is it slow cranking when it gets hot?

I was under the impression after reading the threads here, that the modified advance plate was a Nissan warranty fix for all injector pumps regardless of condition? It is cranking at normal speed when hot - crank, crank, crank, sputter but doesn't catch.