21 replies to this topic

[aguiloco]

Hi, recently after an attempt to climb a ramp for an oil change, I heard a loud CLACK noise, after that, the engine didn't run well. Full history here:

 

https://www.theminif...-carb-problems/

 

 

The engine was running and sounding fine in neutral. I took the car for a spin and something is wrong. Under acceleration, I can hear some muted rattling noise; it sounds like it's coming from inside the engine bay. It is a metallic noise under load; slow frequency, not at the same rate as engine RPM, when coasting, the noise goes away.

 

I jacked the car and took some videos trying to find the source of the noise; I think it comes from the gearbox.

 

 

Here you can hear the engine in neutral and then in gear from inside; there are a lot of noises but I think the extra rattle in gear is noticeable.

 

https://youtu.be/AW-nyGe82qk

 

 

Here from below, I stopped each wheel to discard CV joints, the noise doesn't seem to change.

 

https://youtu.be/BTmuN0tXqIo

 

 

And last, moving the differential by hand, how does it sound to you?

 

https://youtu.be/gGtImYaZhS8

 

I didn't found any broken mount or external source of the noise, so seems like if comes from inside.

 

All help will be appreciated.

 

 

[nicklouse]

My thoughts are there looks to be excessive movement (slop) in the diff.

 

i would be pulling the engine before you pop something through the gearbox housing.

[Spider]

It sounds like the engine has a mild cam and the idler gear is rattling.

I'd also say your diff is in need of an overhaul.

We can try 20 guesses here over the internet from youtube clips, but almost certainly, the engine needs to come out, the flywheel housing and diff removed, possibly the gearbox needs to come off.

[sledgehammer]

If you are going to take the engine out -

I would first take the clutch out first & check FW area

 

that sounded in the idler gear area ?

 

that will need to come off anyway if you need the box to come off

There maybe slack in the diff , but that sounded like idler gear area to me ,

but we are all second guessing over the internet

 

best of luck - hoping for an easy fix

[bpirie1000]

Try dropping the oil see what you have in there...

[aguiloco]

Thanks for your response guys.

Idle gear was rattling at low RPMs but once I tuned the carbs to idle at 800-900 the sound went.

Since the Clack noise I heard was under transmission load I think it comes from there, in neutral the engine sounds better than ever.

It has a new MED lightweight flywheel and clutch assembly, I dodged the bullet when I was able to lap the crankshaft but seems like this time I won't.

I had removed and fixes transmission before in Japanese cars but never took an engine, is going to require a lot of new tools and hours...

[Spider]

It appears daunting, but really, it's not a big deal to remove the engines from these cars.

 

Disconnect the battery.

Remove the bonnet.
Remove the carbs.
Disconnect the exhaust.

Disconnect the heater hoses.

Disconnect engine electricals, including the earth strap(s).
Disconnect the gear linkage.
Disconnect the driveshafts.
Undo the engine steadies.

Unbolt the clutch slave cylinder.
Undo the engine mounts.

Lift the engine out.

 

Depending in the year model, you may also need to remove a few ancillary items as well (eg, washer bottle).

[Designer]

Hi

 

And above all disconnect the speedo drive before you pull the engine out too far. I have forgotten to do it a couple times as you cannot get to it while the engine is in place.

Disconnect it once the engine is about a 1/4 to a 1/3rd of the way out.

 

Paddy

[alpder]

It appears daunting, but really, it's not a big deal to remove the engines from these cars.

 

...Disconnect the driveshafts....

 

Assuming pot-joints, I found the easiest - and least messy - way to do this when on the car is the big-screwdriver-and-hammer method that pops the shaft out of the joint, leaving the inner joint still assembled and on the diff.
 

[aguiloco]

Thanks for the tips guys!

I have the service manual and I will watch a lot of videos, I think I'll manage to get it out.

Now I need to purchase an engine hoist, engine support, etc...

Total time balance so far with my new Mini, 90% repairs 10% drive, this operation will increase that margin a lot.

[aguiloco]

I'll do a compression test before pulling the engine, I think it's burning a bit of oil, maybe that part needs checking too.

As far as I know the engine is a mix of parts, bored block to 1310, aftermarket parts, head from a "race" car, modified gear ratios, etc...

I'm sure I'll find some surprises and be needing a lot of help from you guys.

Edited by aguiloco, 09 December 2024 - 01:07 PM.

[bpirie1000]

Always many heads scratching going on and talking things through on here...

Pull up a problem and we are sure someone will have knowledge..

[coopertaz]

Thanks for the tips guys!

I have the service manual and I will watch a lot of videos, I think I'll manage to get it out.

Now I need to purchase an engine hoist, engine support, etc...

Total time balance so far with my new Mini, 90% repairs 10% drive, this operation will increase that margin a lot.

this is always the way only get a classic if you like being in the garge or on your back in the rain on the drive!"

[aguiloco]

Hello fellow Mini enthusiast, it's been a long time since I last commented here. Life got in the way, and it took me a while to get the right conditions and tools to attempt a repair.

 

First time taking an engine out, it wasn't so bad, step by step, nice and slow.

 

Please forgive the mess in "the shop".

 

 

 

It is covered in oil, I'm going to replace all the gearbox and side gaskets.

 

 

 

There is a lot of splash around the CVD, maybe the cover bush is worn out, another thing to replace.

 

 

 

 

It might be the CVDs leaking grease.

 

 

 

I'm going to drop the gearbox with the engine as it is, so I disassembled the differential to make it lighter. It looks OK at first glance, but I'm going to inspect it better later at the bench.

 

 

 

 

I made a tool to hold the flywheel in place and make the process easier to do by myself. The MED bolt went out fine, nothing moved here, my previous repair seems fine.

 

 

 

I contacted MED to ask about the threads at the flywheel and the distance between them; they are 3/8 UNF, with a CPD of 101.6mm. Unfortunately, I wasn't able to find the correct bolts locally, so I had to order them.

 

I plan to take the complete clutch assembly, I don't want to mess with the balance; it seems like it can be done, right? There are holes in the pressure plate for the bolts to pass.

 

I have a nice hydraulic puller that makes pulling jobs a lot easier. I made a plate with the bolt pattern, and I hope it is strong enough to separate the flywheel from the crankshaft without bending. If it does, I'll try quenching it, or I'll find a thicker plate.

 

 

 

When the bolts arrive next week, I'll be able to disassemble the gearbox and hopefully find out what's the source of the rattle.

 

Also, I'll open the timing chain side to inspect it and replace the leaky gaskets.

 

We'll see what surprises lie inside this engine.

 

 

[bpirie1000]

Have you checked the cv boot joint in the pot joints... may save a large head ache.....