Technical Help with engine mount please

[multiplani]

Having a bit more hassle with my engine mounts...

There is a top mount close the washer & water reservoirs...its like a circular head with rubber in the middle that is bolted to the engine.

The damn bolt loosening!

I haven't bought a torque wrench just yet so have been tightening carefully with a spanner for now until torque wrench is ordered (tomorrow evening).

I have also noticed the rubber looks split about 1/4 way round...does this mean the mount needs replaced?

Just for info...last year my gearbox mount shattered and the engine dropped...got that fixed then few days later knocking all started again...but found it was the bolt on the said top mount that was loose. Tightened it up and never had an issue until this last week...now its loosening almost every day?

 

[maggers]

The alloy gearbox mounts are useless and self-destruct, the earlier steel ones are much better and bolt straight on.

 

[multiplani]

Yeah, I replaced it with a salvage steel one last year.

Regards my query concerning the top engine mount...any advice appreciated.

 

[BikeDoc]

Couple of options.
1. Loctite it.
Take the bolt out, clean up the threads, apply few drops of Loctite to the threads and refit.
2. Lock washer.
Star or Spring type.
3. Lockwire.
Drill the head and wire it to something nearby (e.g. drill a hole in a bracket)
This would be my preferred method, but then I'm an Aircraft Engineer

 

[multiplani]

Thanks for the advice. Might just Loctite for now.

What about the rip in the rubber centre...it be ok for a while???

And can this particular mount be bought from anyone other than FIAT??? I don't know what its called but can't find any suppliers online (for this particular mount).

 

[BikeDoc]

It's more of a 'steady' than a proper mount, it takes no weight, but stops the engine 'rocking' back-and-forth.
There won't be much side-loading on the rubber, so a split should be OK for a wile, but it will get worse.
You could superglue the split for now.
I'd take it off, and get some superglue right into the split, stick a thin screwdriver into the split and work the glue right in.

If you can find some thick (5mm or so) rubber sheet, or maybe some large enough rubber washers (e.g. like giant tap washers), you could 'sandwich' the damaged end with them.
E.g. put a rubber washer between the mount and the steady, then another on the other side with a large steel washer under the bolt head.
You'd need a slightly longer bolt.

 

[multiplani]

Back online at last....computer issues on top of it all!!!

Bikedoc...don't suppose you know what I should torque the bolts to?

 

[BikeDoc]

Is it just the forward bolt that's loosening?
That one bolts into an Alloy fitting, check the threads in the fitting carefully for corrosion, and clean them out as best you can before refitting the Steady and Bolt.
Try the Bolt in the Fitting without the Steady in place, see if there's any play/wobble with it screwed in as far as it would be with the Steady fitted.

I can't recall if they're 8mm or 10mm Bolts.
I'd say around 10ft/lb [13Nm] if they're 8mm, or 16ft/lb [20Nm] if they're 10mm.

As for the rear one it's a basic Steel Bolt going into a Steel thread, so you can use the 'generic' Torque loading for it's size...
Metric Bolt Torque figures...
Torque conversion chart...
As you're using Loctite, use the 'Lubed' column(s) in the first chart.
So around 15ft/lb [20Nm] for 8mm, 28ft/lb [38Nm] for 10mm.

 

[multiplani]

I feel like an idiot now...didn't even know there was a generic torque guide for steel bolts.

Yeah, its the front one into the alloy.

Thanks for that...another step closer to becoming competent.

 

[BikeDoc]

...didn't even know there was a generic torque guide for steel bolts...

There will be generic charts like that for all common fastener and fitting material combinations and sizes.