Helicoil inserts

pandos

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I am in need of two bolts to hold my flywheel onto the crankshaft...it's an md21 b .

I wrecked one bolt to get it out and lost another.

I ordered bolts from a french supplier but what arrived are m10 not m11 as the originals. (It maybe that Volvo upgraded the bolts when they marinised the Peugeot based engine)

M11 are not available through Volvo or any site I have checked.. (.some pretend they are in stock until you go to check out and then say not in stock...)

Query...could a helicol insert convert the m10 up to an m11?.

The alternative is an m11 metric fine bolt forced into the ordinary metric hole...(m 11 metric fine bolts in flywheel of xc90).

All constructive suggestions welcomed...
 
Unfortunately an M10 helicoil bit will be smaller than 11mm. You could drill out the hole and tap it to M12 if you can obtain that size.

Don't force an M11 fine thread into an M11 standard/coarse.

You should be able to order M11 coarse thread bolts online. Just buy over-length and cut down to size if needed. This kind of thing: Genuine GM LS Flywheel Bolt M11 x 1.5x23.5 Long 11569956 | eBay but it depends upon exactly what pitch your M11's are.

Richard
 
I am in need of two bolts to hold my flywheel onto the crankshaft...it's an md21 b .

I wrecked one bolt to get it out and lost another.

I ordered bolts from a french supplier but what arrived are m10 not m11 as the originals. (It maybe that Volvo upgraded the bolts when they marinised the Peugeot based engine)

M11 are not available through Volvo or any site I have checked.. (.some pretend they are in stock until you go to check out and then say not in stock...)

Query...could a helicol insert convert the m10 up to an m11?.

The alternative is an m11 metric fine bolt forced into the ordinary metric hole...(m 11 metric fine bolts in flywheel of xc90).

All constructive suggestions welcomed...

Could a machine shop make them from scratch for you on the lathe. Or even re- diameter a m12 down and recut the thread. Buy them overlength and cut off the thread portion and reduce down and re thread what was the unthreaded part. Head size would be wrong but who cares.
Do they need to be hi tensile or other exotic property?
I seem to remember that some french cars used 11 mm for head bolts way back when I was messing with them but they would probably be wrong lengths and thread lengths anyway
.
 
No. Helicoil won't do the job. Plenty of M11 bolts available on e bay.
Just need to make sure you get High tensile and the right length
 
Unfortunately an M10 helicoil bit will be smaller than 11mm. You could drill out the hole and tap it to M12 if you can obtain that size.

Don't force an M11 fine thread into an M11 standard/coarse.

You should be able to order M11 coarse thread bolts online. Just buy over-length and cut down to size if needed. This kind of thing: Genuine GM LS Flywheel Bolt M11 x 1.5x23.5 Long 11569956 | eBay but it depends upon exactly what pitch your M11's are.

Richard
Thanks for that I think you are on the right track. The helicoils would be too easy... Drilling and tapping would be a huge pain and would only end in pain..

Engine currently in saloon waiting for two bolts??

Searching for flywheel bolts must have been too obvious for my grey matter....

I hate eBay because it will take ages to get to Ireland..all with the object of making money on the transport...

But the Opel main dealer might be worth a visit...

Many thanks to all the contributors..
 
French engine builders use some very unusual bolt sizes. I thought it was a Citroen speciality but it seems Peugeot think the same. My 2CV engine has many M7 bolts and studs, and so many 11 mm, 14 mm and 16 mm heads and nuts that I have had to buy extra spanners to supplement sets that do not include them.
 
All sorted. Opel main dealer found some old stock in Germany...but even better, I found a Ford reference from ebay and my local ford main dealer had 4 on the shelf so problem soved for 12 euros...(just made 2 hour round trip to check they actually fit)

When I am finished the work I'll put up a post with details of what parts I used in the rebuid and the suppliers... Might help to keep someone's original engine ticking over...

Thanks
 
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