[hooki]

hi,

after going out yesterday my sierra seems to have a few problems. First is a very rough idle. Happened after going through some muddy water. I have so far cleaned all the points on the rotor cap, cleaned out the carby with some carby clean and check plugs and leads nothing seems to be able to get the idle back to normal. It also sounds like there's a slight miss at idle but it drives fine and pulls like normal......any ideas what the problem could be?

Also, i dont have a picutre atm, but on the underside of the gearbox, towards the from of the bell housing there is slit in the gear box, about 15mm x 3mm which is there from factory. After wheeling for a while oil started to drip out of there, was a constant drip every few seconds....now has slowed down a bit but hasn't stopped......any ideas what this could be?

cheers.

[Damo]

hooki wrote:

hi,

after going out yesterday my sierra seems to have a few problems. First is a very rough idle. Happened after going through some muddy water. I have so far cleaned all the points on the rotor cap, cleaned out the carby with some carby clean and check plugs and leads nothing seems to be able to get the idle back to normal. It also sounds like there's a slight miss at idle but it drives fine and pulls like normal......any ideas what the problem could be?

Also, i dont have a picutre atm, but on the underside of the gearbox, towards the from of the bell housing there is slit in the gear box, about 15mm x 3mm which is there from factory. After wheeling for a while oil started to drip out of there, was a constant drip every few seconds....now has slowed down a bit but hasn't stopped......any ideas what this could be?

cheers.

Rear main seal perhaps?

[Rockhopper]

yep. Sounds like the rear main seal on the engine, and the bad idle sounds like one of you ignition leads shorting to earth. Give your ignition system a blast with compressed air, especially the leads around the spark plug holes and the dizzy cap. If you have any oil, dirt or grime on the cylinder head around the spark plug holes, clean it up as it creates an easier path for any stray spark to get back to earth.

[hooki]

for the rear main seal to go, wouldn't that mean that my clutch would be slipping?

I'll give the plug holes a good clean and see it that works.

[Rockhopper]

hooki wrote:

for the rear main seal to go, wouldn't that mean that my clutch would be slipping?

No

[hooki]

i gave the ignition system a good clean and still no luck with the idle. Any other ideas wat it could be??

How hard are rear main seals to change?....expensive?


thanks.

[Rockhopper]

Not that hard, but a pain in the bum. Gearbox, clutch and flywheel all have to come out. Providing there is no scoring on the crankshaft, you should be able to replace the seal and all will be good.
As for your idle problem, it maybe just coincidence that you may have got a bit of crap in the carby. Two things that you can do that may fix the problem. Pull the air filter cover off the top of the carby and start the engine. While using one hand to operate the accelerator, use the other hand over the top of the carby when giving it a rev. The vacuum it creates might dislodge any shit in the carby. The other method is to pull the air filter cover off the top of the carby again. Reverse ignition leads 2 and 3 and start the engine. Give the engine a rev and it will backfire through the carby hopefully dislodging any crap down there. If you've never done this method before, be aware it will probably scare the crap out of you when you hear the noise and see flames shooting out of the carby, which is exactly why you should never put your face over the top of a carby to see what is happening down there. If the engine stalls and there is still fire coming out of the carby, don't despair, just crank it over and the vacuum created by the engine should put it out. I've used both these methods over the years with great success, but I personally prefer to put my hand over the carby.

[hooki]

reversed the leads as you said 'rockhopper' and gave it a rev and it now runs perfect. thanks for you help rockhopper.

will hopefully get onto the rear main in the next few weeks. Just wondering if it's alright to drive around with even though it drips out a little??

[Rockhopper]

As long as you check the engine oil level regularly, it should'nt really be a problem.

[shep]

i own a Mitsubishi v6 so i know a bit about oil leaks
nulon make a stop leak product that works in my wagon, chuck a bit in
and see how it goes.