Return on accelerator sticking and drive to rear wheels appears intermittent

Dvaepat4

Active member
Hi there, I've moved onto my next project, a 2007 rtv 900, ex fruit farm and ex kids playground toy! It has had a harsh life but I've managed to acquire it and am willing to try and fix it. Fuel tank was full of sand so removed and flushed out, removed sand from air inlets etc, put new battery on and after about an hour tinkering have managed to get it starting off the key! Not bad given not run for three years or so! Next problem, broken rear CV joint to rear axle. Axle removed and engine started - sometimes drive to rear wheels sometimes not...when there is drive to rear wheels I tried to stop manually but pushing out well and cannot stop it. Another issue is I cannot remove from gear once in gear unless I stop engine?? Are these issues linked? Hoping it is a relatively easy fix. Didn't want to spend lots of money on new drive joints then discover gear box is knackered!! Any advice would be appreciated. Suspect removed from farm due to issues but then put ibro farm play park for kids to play/climb on! Thank you.
 

aurthuritis

Well-known member
Site Supporter
need to check and see if the pressure relief poppet on the HVT is stuck. does it have the pull knob on the dash to relieve the HVT pressure? if not it will be attached to the brake actuator on the right rear of HVT. can't shift out of gear is probably a simple adjustment. will it shift in and out of any gear with the engine off? since there is a differential in the rear you will probably have to replace the driveshaft before you proceed.
 

Dvaepat4

Active member
Hi there again! I've tried to attach photos but getting admin message (hopefully will follow once resolved). It moves in and out of gear well when the engine is off but it sticks in gear when engine is running. The diff was seized but been working it with oil and moving a bit more freely now. Can't find poppet although there is a space where one may have been but then broken off! Is right rear drivers side? So suspect I need to drain HST down then pull out drive shaft? Why would drive only engage sometimes? Any ideas why accelerator cable is not returning? There is a ram type device on the back end - is this perhaps faulty and not pushing back?
 

aurthuritis

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Site Supporter
there is a spring return for the peddle and driver cable but there is a dampner attached that i think you describe. either take the dampner loose or get some oil in it and work it until you know it is free. you might need to check and see if the diff lock is engaged and stuck before you disassemble. the reason it won't shift out of gear is a simple adjustment to the peddle cable and speed control lever. i would first check for rusted sand choked stuck linkages on the diff lock and drive cable dampner. could be a very simple fix. if the pressure relief poppet is broken missing it is a simple fix but most likely just stuck and needs free up with oil and light tapping. do you still have the workshop manual???
 
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Dvaepat4

Active member
General photos
 

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Dvaepat4

Active member
I suspect CV joints are beyond repair....they are heavily worn and unlikely to get new spiders to fit? It must have been driven for ages clattering about!
 

aurthuritis

Well-known member
Site Supporter
yea those U joints are junk. but in a pinch you might be able to make them work. could check ebay for some used ones.
 

Dvaepat4

Active member
Is this device supposed to push out or pull in? Doesn't seem to do either - is this why accelerator is not returning?
 

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aurthuritis

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it has been a while but i think that is it. is it connected to the control linkage? found the relief valve yet?
 

Dvaepat4

Active member
The rusty looking hex bolts?
 

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aurthuritis

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wait a minute i told you all wrong!!!! yes that is the pressure relief valve. sorry i was thinking of the X model. and i can see that you do not have the dash mounted pull cable to manually operate it. the way it is supposed to work is when you push the brake peddle the movement of the brake lever on the side of the transmission pulls on the spring and overcomes the pressure on the poppet valve and bleeds residual pressure in the HST at idle. allowing easy gear change. even at best it doesn't work all that great and most gear change problems can be overcome by adjusting the hst control cables. get to that later after everything is freed up good.
 

aurthuritis

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Site Supporter
i just looked at the picture again and i can see a broken heim joint. that is where the cable on the dash connects to the pressure relief valve. so you do have the knob on the dash but the cable is broken.
 

aurthuritis

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also looks like it might be possible that the brake levers are sticky and causing the relief valve to be depressed some. this could cause the drive problems you described.
 

aurthuritis

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just to help clear things a bit. the pressure relief valve on this model is on the extreme lower left rear of the transmission as you face the machine from the rear. sorry. spray the two valves with penetrate oil and carefully work them in and out with the engine shut off until they both pop back out and stau out but push in freely. same same for the levers that actuate them
 

Dvaepat4

Active member
Great thanks. I have also just realised the handbrake was on (I know....dont say anything - I thought it was off!!). So this may be cause of intermittent drive. Will test again tomorrow! Do I need new relief cable or is that an optional extra?!
 

aurthuritis

Well-known member
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no you don't need the cable yet but it is a great option to aid the shifting if you stop on an incline.
 

Dvaepat4

Active member
I noticed that with the other you helped me fix. You have to select gear wisely before tackling a hill. If I select high and take a steep hill it will grind to a halt and it is difficult to release / change gear.
 
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