Power loss

[Fouldsy67]

Good evening all I have a GQ RB30 carby rig driving it seems to lack power takes a long time to get any speed up and drops back to around 70 going up any hills
Starts and idles great has extractors 2 1/2 inch exhaust plugs seem fine all set to 0.9 mm fuel pumps good sits at 30 psi revs free at stop no missing compression is all around 165psi cold just stumped on what it could be any help would be helpfull
Cheers in advance

[mudnut]

Good evening all I have a GQ RB30 carby rig driving it seems to lack power takes a long time to get any speed up and drops back to around 70 going up any hills
Starts and idles great has extractors 2 1/2 inch exhaust plugs seem fine all set to 0.9 mm fuel pumps good sits at 30 psi revs free at stop no missing compression is all around 165psi cold just stumped on what it could be any help would be helpfull
Cheers in advance

Have a look at this thread. There is quite a bit of info about the carby in it. I found the second stage butterfly was sticking or not opening properly. http://www.nissanpatrol.com.au/forum...-Helpful-Hints

[mihit]

manual? auto? (clutch slip? TC issue?)

[Fouldsy67]

Manual and just found a box in the back with 3 carbys in it clutch is good no slipping there

[mudnut]

Manual and just found a box in the back with 3 carbys in it clutch is good no slipping there

The carbies playing up is a common thing for these old buses. I've been on the lookout for a spare carby so I can put a kit in it and keep it for long trips in remote areas.

[Big Girl]

Same problem, diesel 3L GU 2004. It seems to know when it's close to home and does it on the same hill every time! On the third MAF sensor. New air filter and thorough clean of the intake. She will be coasting along fine then suddenly loses a little power, like she is suddenly driving into the wind. And she does it constantly when towing the caravan! Any ideas welcome. No we haven't done a diagnostic, that's next.

[mudski]

Same problem, diesel 3L GU 2004. It seems to know when it's close to home and does it on the same hill every time! On the third MAF sensor. New air filter and thorough clean of the intake. She will be coasting along fine then suddenly loses a little power, like she is suddenly driving into the wind. And she does it constantly when towing the caravan! Any ideas welcome. No we haven't done a diagnostic, that's next.

Possibly a boost leak. Are you running the original intercooler?

[Big Girl]

Possibly a boost leak. Are you running the original intercooler?

Yes. Had the head replaced last year. Will contact the shop and book her in for diagnostics. What are your thoughts?

[mudski]

Yes. Had the head replaced last year. Will contact the shop and book her in for diagnostics. What are your thoughts?

Well if you are running the original intercooler, I would say its leaking. Check the underside of the cooler. Is is clean? Or does it have oil deposits on it.

[Big Girl]

Well if you are running the original intercooler, I would say its leaking. Check the underside of the cooler. Is is clean? Or does it have oil deposits on it.

Thanks heaps Mudski, much appreciated. I did some research and will get under the bonnet this afternoon. Regards, Louise