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Gearbox Bearing Noise And Coolant Flow?

467 Views 7 Replies 3 Participants Last post by  Ronniebiggs
Just trying to combine a couple of questions into 1 post.

Firstly my gearbox is making a bearing noise? I have just rebuilt it and it has no oil in at the moment but when I press the clutch it goes off. Sounds like the release bearing could be worn but I never noticed it before I stripped the engine and box. Any ideas on this one? Really hope its just the lack of oil as I really could do without parting the box and engine again. Especially as this time I would have to part it in the car.

Secondly my coolant flow. I had a blockage where the pipe at the bottom of thermostat meets the block. It was blocked solid so I pushed a fine screw driver through it but im worried that the flow might not be working. Which way does the water flow? from thermostat down the pipe into the block near all the belts and things (Its the pipe that usually runs along close to the pulleys and is notoroius for leaks?

Many Thanks
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One thing I would like to add is that I put a new spigot bearing in and I never pressed it tightly home in the flywheel. As dumb as it sounds I placed it in the flywheel and assumed that when the gearbox goes in it would press the bearing home. It was a new bearing and I have read a worn one of these will create the bearing style noise I can here. So im assuming it could be this as it might not be pressed home.

Any thought would be most welcome as I plan on removing the box again and im not looking forward to have to go through the procdure again.
Im going to start to take the box out again later this afternoon. Could anyone confirm or comment on if they think it is the spigot bearing thats loose (as I didnt press it into the flywheel I placed it by hand!) or the release bearing making the noise or simply the fact I have no trasnmission oil in?

Most appreciated
Why are you running the box without any oil in it? that's asking for 'funny noises' to start isn't it.

I pushed the spigot bearing flush with the flywheel, I don't think the gearbox will do it for you, though I may be wrong.
Why are you running the box without any oil in it? that's asking for 'funny noises' to start isn't it.

I pushed the spigot bearing flush with the flywheel, I don't think the gearbox will do it for you, though I may be wrong.
Thanks for the reply. The box has no oil in because I had to drain it to remove it the first time and I didnt want to put oil back in until I was sure I had no problems or I would have had to drain it again to get it back out.

I keep thinking is the noise because there is no oil but it goes off when you press the clutch. I dont like to admit it as I cant imagine how many knuckles im going to end up scrapping, but it sounds like Im going to have to take the box back out and make sure the spigot bearing is pressed home properly. Just hope the release bearing is ok as I will go mad if I put it back together to find out the release bearing is the cause.

I have a spare one but again its 2nd hand. I might chance a swap with that and see if it makes a difference.
Here's a coolant flow diagram for you:

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Here's a coolant flow diagram for you:

Thanks thats exactly what I needed!

Looks like the coolant flow is ok based on the diagram. Now all I need to do is try and blow through the block to make sure its not blocked.

Just stipped the box back out and the spiggot bearing was just dangling there not even in the flywheel. I suspect that this would have caused my problem and so Im now building it back up to try again. One thing I noticed is the pressure plate nuts where not very tight. I did torque them up and they were not loose but they didnt take much to get off.

Looked on one site and it says torque setting of 14-19 lb/ft. That doesnt seem much.
Just an update. I pressed the spigot bearing into the flywheel dropped the gearbox on my hand, to find out the noise is still there!!

It is slightly quieter and im hopeful that it will go completely when I add the new hydraulic oil. I checked the release bearing and it didnt appear to be worn and I never noticed any noise from it before.

So Im going to fill it with oil and see if the sound is there. If it is then I can only imageing some water from the rain has got past my plastic sheets I used to cover it whilst the engine was out and the bearing has become worn. If thats the case then im leaving it!!

Certainly for a while and maybe one day when im bored I might tackle it again.
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