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-   -   GRP... Engine... Thread... (https://www.rctech.net/forum/offroad-nitro-engine-forum/211114-grp-engine-thread.html)

zixxer 01-11-2009 10:56 AM


Originally Posted by AndyItalia68 (Post 5278488)
Yes, now Amain is selling the old GRP engine at a lower price... But for the new engines, small distributors will be able to make a better price than a big distributor as Horizon? Just incredible :confused:


it is awesome as the rc guy now gets nice stuff at good prices ...unless there quality goes down .....

captain america 01-13-2009 12:19 PM

Does anyone know which type of Fiorini/OT cooling head (if any) will fit on the .21 mill? I don't particularly care for the bland silver one that comes with the non-tuned version.

glolar 01-13-2009 05:33 PM

GRP increasing idle
 
All,

I am running the GRP modified, and it runs great, but after revving and returning to idle, the idle starts increasing steadily, and keeps increasing until it is very high. Revving the engine about half throttle calms the idle down again briefly, but then it starts rising again.

I have tried tuning both needles (both ways) and the same with the idle screw, and cannot get rid of this problem. Richening the low end seems to work the best, but then the low end is too rich. (Note I always warm up the engine before trying to adjust any of the needles).

Any help is appreciated.

Thank you in advance.

Joey Platinum 01-13-2009 05:40 PM

Jonro ..did you get the bearing race out,and how??

SupermaxxRich 01-13-2009 06:26 PM


Originally Posted by glolar (Post 5289224)
All,

I am running the GRP modified, and it runs great, but after revving and returning to idle, the idle starts increasing steadily, and keeps increasing until it is very high. Revving the engine about half throttle calms the idle down again briefly, but then it starts rising again.

I have tried tuning both needles (both ways) and the same with the idle screw, and cannot get rid of this problem. Richening the low end seems to work the best, but then the low end is too rich. (Note I always warm up the engine before trying to adjust any of the needles).

Any help is appreciated.

Thank you in advance.

sounds like it could be a air leak, try sealing everything with some air seal. carb, backplate, pinch bolt.

underway 01-13-2009 06:46 PM


Originally Posted by glolar (Post 5289224)
All,

I am running the GRP modified, and it runs great, but after revving and returning to idle, the idle starts increasing steadily, and keeps increasing until it is very high. Revving the engine about half throttle calms the idle down again briefly, but then it starts rising again.

I have tried tuning both needles (both ways) and the same with the idle screw, and cannot get rid of this problem. Richening the low end seems to work the best, but then the low end is too rich. (Note I always warm up the engine before trying to adjust any of the needles).

Any help is appreciated.

Thank you in advance.



Is your throttle linkage pulling the slide open slightly? Pull off air filter and go from full throttle to brake and release.

glolar 01-13-2009 07:42 PM

I don't think anything is binding or rubbing, but I will check. My guess was an air leak too. I have already ordered some sealant. I will let everyone know how it turns out.

Thanks guys.

white48rc 01-13-2009 08:34 PM

Make sure its not sucking air through the front bearing.Take the fly wheel off and spray some soapy water on the front bearing and spin the crank back and fourth. if you have bubble blowing up it has a air leak.Another racer showed me this trick and i found my air leak.

zixxer 01-14-2009 06:12 PM


Originally Posted by white48rc (Post 5290077)
Make sure its not sucking air through the front bearing.Take the fly wheel off and spray some soapy water on the front bearing and spin the crank back and fourth. if you have bubble blowing up it has a air leak.Another racer showed me this trick and i found my air leak.

nice trick there ...and also it sounds like an airleak ....

Marcus Falconie 01-15-2009 07:15 PM

carb
 
Have any of you guys used a different carb on a GRP. My carb is broken but I have OS, Novarossi, and a Vega carb will the motor run with a different carb. Thanks

Jonro 01-15-2009 08:00 PM


Originally Posted by Joey Platinum (Post 5289252)
Jonro ..did you get the bearing race out,and how??

Nah lol tried everything but it wouldent budge, so i just dumped it on my engine modder as he was going to be replacing the bearings and modding the engine anyway, he said it wouldn't a problem to get out, with the tools hes got.

Just got the engine back a couple of days ago and everything looks good, about give it a run now.

glolar 01-16-2009 12:39 AM

Zixxer,

What did you do to fix the air leak ... replace the bearing?

zixxer 01-16-2009 03:22 AM


Originally Posted by glolar (Post 5300339)
Zixxer,

What did you do to fix the air leak ... replace the bearing?

hey buddy didnt have an airleak:confused:but the trick about the saopy water around the bearing and watching for bubbles is good ...and if you did get bubbles i would say that would be what you would do ....:)

glolar 01-16-2009 10:37 AM

Sorry zixxer, I meant to address my question to white48rc ... :eek:

white48rc 01-16-2009 10:47 AM


Originally Posted by glolar (Post 5301663)
Sorry zixxer, I meant to address my question to white48rc ... :eek:

Make a long story short I had to replace the block and bearing.


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