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Scottish888 wrote: Another great tip, I may have some large rawl bolts left over from my last construction project.

A Fischer fastener, 16mm diameter, did the trick. I assembled and tightened the fastener in the bearing without its plastic ring, making sure only the cone showed on the 'blind' side. All in the oven to heat, out on the bench and tapped the fastener out from the 'blind' side which took the bearing with it. And the fastener remains re-useable - cost €1.40.

My apologise for resurrecting this old chestnut!

Trying to remove that blind gearbox input shaft bearing from the right hand case of the late 1975 350MKIII engine.

I have gradually heated the cases in a fan oven to 100°C, 110°C, then 120°C and finally in desperation, to 130°C./ Whilst using both a slide hammer blind bearing extractor and the old 'Rawbolt' trick, so that the bolt protrudes through the pushrod hole and can be hit with a 2lb hammer and punch on the end of the bolt. It doesn't want to budge! And both extractors 'pop' out from the inner race, even after tightening up. There appears to be very little gap behind the inner race for the puller to get a grip on the back of the race! Whilst the 'Rawbolt' taper is just polishing the inner race surface!

All the other bearings popped out at the 100°C temperature.

I know from previous experience that these can be bar stewards and the 450 MKIII has had the ubiquitous 2 holes drilled through the crankcase, so that a straight puch can be used to knock the bearing out from the outside. Not by me I might add, but it has never proved a problem to remove the bearing from a 110°C heated case. A wee squeeze of silicone seals up the holes, once the new bearing is in place and the case has cooled, causing no problems, so far.

Am I to resort to the case drilling, or should I go down the 10mm bolt head welded to the bearings inner race puller technique, as the last chance saloon?

Thank you for your time.

Good health, Bill

In the past I have had to resort to using the dremel on blind bearings to split the outer ring. Slow and requires a lot of patience but it did the job. Good luck

I went the drilling and punch method. I then used jb weld to fill the holes with a blank washer in the inside to protect the seat of the outer race when fitted. So far so good!
I was worried I was causing more damage with the extractor slide hammer …
Best of luck

Dave

Bill, just weld a bolt into it......I assume you are going to scrap it anyway (the bearing I mean ) when for whatever reason its that tight in the case (maybe loctite? though enough heat should destroy the bond) drilling two little holes may not give you enough access to drive it out and you would probably have to weld the bolt in trick anyway, ...........good luck with it.
Cheers,
George

Thank you All,

Saturday morning I will try the 10mm bolt trick. The blind cam shaft support bearing is going to get the same treatment! That has been equally stubborn.

I will post an update.

Bill

Crankcase heated to 120°C and torque applied to the welded 10mm bolt! Loud "CRACK"! Snapped flakes off the hardened inner bearing race, the bolt came free and without moving the bearing a micron!

I think the nice new sharp drills are coming out!

Good health, Bill

Bill before you start drilling holes why not try dremel and small diamond bit to grind slot in outer race to release pressure. If the bolt failed so will a small punch through hole.

Bill, ok so the welded in bolt didn't work for you.....that surprises me......this has always worked for me, how did you weld the bolt in? so here's another way to try, get a slug of steel bar or a big allen screw head and weld that into the bearing inner race, don't just tack it, really weld in in! heat the case and use a drift to drive it out from the outside. See how that goes, or just try welding the bolt in again.
(I know this is a stupid question) did you use a big enough diameter sleeve to allow the bearing to get out?
Cheers,
George

Aye George and George,

The problem I have with the welding is that my neighbour has the welding gear and is largely self taught and agricultural, both by nature and the work carried out. He also gets "excited" and tends to rush at the job and if it moves or doesn't quite go correctly, bashes on and then shrugs his shoulders!

So, off to see a "professional" tomorrow and receive "dogs abuse", plus a cash fee of ??????? I know that gas and time cost money these days, but some of these "professionals" are milking it and charging the full £50 hourly rate for a 10 minute, cash backhander that never sees the light of day in the books.

I used a 37mm socket across two pieces of seasoned Scottish oak that showed no impression after the bearing race had flaked. I like the lateral thought of bunging up the hole in the bearing and then battering it from the outside after "cooking" in the oven. So that is the likely next move. Maybe I'll be saved the dental work with a Dremel and the fine diamond bits?

Good health and thank you for your time and inspiration, Bill