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Poor starting when hot,

Posted: Tue Apr 03, 2018 5:30 pm
by Razor
I have read a few questions and answers about poor starting when hot but I feel this is slightly different,I have a 1995 2.5diesel auto,when I first start in the morning itโ€™s starts almost instantly,after about 45 to an hour running with the temperature sitting firm at 11 oโ€™clock and I need to slow down or become stationary the revs drop to less than 500rpm become irrational and sometimes cuts out then starting can take some time,the engine turns over fine but does not fire up,leave it for ten to 15 min and it normally starts,but obviously this is a problem when driving in traffic on a slow road.i have replaced the fual filter and air filter this dose t seem to have made any difference.any help greatly appreciated, :)

Re: Poor starting when hot,

Posted: Tue Apr 03, 2018 5:40 pm
by teenmal
The first thing I would check is the Air/clack valve in the fuel cap, even try running the vehicle without the cap.

Take care

Re: Poor starting when hot,

Posted: Wed Apr 04, 2018 8:22 pm
by Razor
I have removed the fuel cap and dismantle and cleaned today so will try tomorrow and see what happens,
Thanks๐Ÿ˜Š๐Ÿ˜Š

Re: Poor starting when hot,

Posted: Sun Apr 08, 2018 4:50 pm
by Razor
Well I have done all that has been suggested with no positive outcome,wiped all the muck away from underside of the pump then ran it for 30 min then wiped under the pump again sines of diesel not a lot but it was there,have ordered a pack of the two o ring seals will try and change these any tips would be appreciated. I also spoke to bongospares who said I would need a reconditioned pump as when the pump heats up the diesel leaks causing starvation when on tick over and as the seals only last a couple of months,what are other views who have replace the seals?.thanks 8n advance,

Re: Poor starting when hot,

Posted: Tue Apr 10, 2018 12:29 pm
by bongotoffee
teenmal wrote: Tue Apr 03, 2018 5:40 pm The first thing I would check is the Air/clack valve in the fuel cap, even try running the vehicle without the cap.

Take care
I read this post yesterday and fixed my warm starting problem by loosening the fuel cap. I was having to wait an hour after a run to start again!

Many thanks teenmal.
:D

Re: Poor starting when hot,

Posted: Sun Apr 29, 2018 7:17 pm
by Razor
Hi all thanks for your comments,her is my latest update,
1,back and front seals replaced on injector pump,
2.fuel cap valve cleaned/removed,
3.replace diesel return hose from injectors
Fuel filter,banjo filter cleaned replaced,
From cold car starts perfect when up to temperature on short runs if I stop and start no problem,it is only after a continuous drive of 30min+ that if I slow down in traffic the rev,s drop and if left the car dies and then it is difficult to stat but always does with a few puffs of blue smoke and the runs fine util I slow down again.
I have phone around a couple of diesel fitters and have been told it is most likely the injector pump needs replacing
Your thoughts please as I am out of things to try,๐Ÿ˜Ÿ๐Ÿ˜Ÿ

Re: Poor starting when hot,

Posted: Sun Apr 29, 2018 8:08 pm
by BongoBongo123
Not an expert here. It is a long shot and there are zero guarantees but a can of BG244 just to clean through the fuel system
might be worth a shot. Worst case you blew ยฃ23.00

I think fuel pumps (Diesel) seems between ยฃ500-600.00 a pop. Of course you need an expert you can trust to diagnose it
before spending out on anything.

Good luck.

Re: Poor starting when hot,

Posted: Sun Apr 29, 2018 8:27 pm
by Billybongo123
May also be worth running on a separate gravity fed drum of diesel directly to the pump inlet to rule out air ingress or vacuum issues. That way you are sure it's the pump and it's clearances. Just a thought.

Re: Poor starting when hot,

Posted: Sun Apr 29, 2018 11:13 pm
by Northern Bongolow
if you look on the drawing below for item 42-590a and click on the number it will highlight in the left margin that it is a mounting and valve for the evap of fuel vapours. this clips onto the inside of the chassis rail level with the front of the gearbox, its hard to spot coss its usually been covered in road grime and underseal products, it clips onto the chassis in a small hole, pull it away from the chassis and remove from the pipe end and wash out they are usually blocked.
before you refit it, in the end of the pipe (or a little way inside) is a hidden and not mentioned anywhere one way valve, warm the pipe up with hot water then remove the thimble sized one way valve, wash out/blow through as this is usually blocked then refit the correct way round as removed, assemble and click back into chassis. done.

http://lushprojects.com/bongopartsmk2/c ... mgno=.html

i think the little piece next to the part mention above in the drawing is the valve in question but ive never heard it mentioned. i found it years ago while fixing a ladys bongo, she had spent hundreds of pounds trying to sort your problem along with all the down time and unreliability stress she was about to give the van away. this fixed it. 8) .

try it, its a free fix if it works.

Re: Poor starting when hot,

Posted: Mon Apr 30, 2018 11:49 am
by Razor
Any thanks for your replyโ€™s and help is this the check valve required?
Kind regards

https://www.amazon.com/Mazda-NC49-42-59 ... B00KWEOQ6I

Re: Poor starting when hot,

Posted: Tue May 01, 2018 8:58 pm
by Razor
Valve checked all ok so it looks like I need another pump๐Ÿ˜ข๐Ÿ˜ข
Thanks one and all I will remove it tomorrow and look for a good replacement.

Re: Poor starting when hot,

Posted: Tue May 01, 2018 11:52 pm
by Northern Bongolow
that is the outer valve that clicks on to the chassis leg but there is another thimble type one that is up inside the pipe that this fits too.

Re: Poor starting when hot,

Posted: Fri May 04, 2018 8:05 pm
by Razor
Well a hard day on the bongo today, injector pump replaced with secondhand unit that has been refurbished and now up and running,six hours from start to finish,managed to pull the fuel through the pump by connecting a small vacuum pump on the return and the cracked no4 injector connection and after a few turns she fired into life,happy days I hope,
Thanks one and all for your help,just hope this has sorted the problem but will post on here in a few day,

Re: Poor starting when hot,

Posted: Sat May 05, 2018 10:33 am
by mikeonb4c
Razor wrote: Fri May 04, 2018 8:05 pm Well a hard day on the bongo today, injector pump replaced with secondhand unit that has been refurbished and now up and running,six hours from start to finish,managed to pull the fuel through the pump by connecting a small vacuum pump on the return and the cracked no4 injector connection and after a few turns she fired into life,happy days I hope,
Thanks one and all for your help,just hope this has sorted the problem but will post on here in a few day,
Great news - hope that finally sorts it!

Re: Poor starting when hot,

Posted: Tue May 08, 2018 7:52 pm
by Razor
That problem seems sorted but now to fine tune the timing as I can only rev to3500rpm before its starts to misfire when previously I could hold 4000rpm also the kick down is not as responsive any help greatly appreciated ๐ŸŸ๐ŸŸ