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Moritz
05-07-2019, 03:46 PM
In each of two attempts I've broken one of the water pump quarter inch bolts. Different holes. Fortunately it's in the timing chain housing and the first (just broke the second today) was easily removed by a local machine shop. The second attempt I tried to do everything super hygienic, cleaning out the bolt holes, using anti seize and I really didn't think I was torquing it too much, and yet.

What is the recommended torque????

Feeling a bit like Sisyphus at this point...oh, doesn't look like I'm the first on this engine I've owned for 32 years as a couple of the holes already look like they've been helicoiled, pre 1987

1974 Series 3 88

mearstrae
05-08-2019, 07:28 AM
These don't take much torque. Grade 2 (no head markings) course: 4 lb/ft, fine: 4.7 lb/ft. Grade 5 (three lines on the head) course: 6.3 lb/ft, fine: 7.3 lb/ft. So, a little extra twist of the wrist will easily break these. Also, if the treads don't match. You should be able to screw in by hand most of the way in.

'99 Disco II
'76 series III hybrid 109
'95 R.R.C. Lwb (Gone...)
'70 Rover 3500S (Gone...)

erik88lr
05-08-2019, 07:42 AM
Land Rover doesn't provide specs for torque for these bolts, as they're normally just tightened "by feel".

I'd suggest using an appropriately sized wrench or ratchet. If you look at your set of wrenches the one for a 7/16" headed nut or machine screw is quite short - to limit the amount of torque applied. If you use a foot long ratchet instead to tighten the fasteners there is a risk of over-tightening and breaking them. I have a delicate looking little Snap On 1/4" drive ratchet that does a great job for applications like this.

jp-
05-08-2019, 04:32 PM
I have a delicate looking little Snap On 1/4" drive ratchet that does a great job for applications like this.

+1

I use a small 1/4" ratchet on anything 1/4" or under, and 5/16" if it's not grade 8.

Reminds me of that old joke: What's the proper torque for a valve stem cap? Tighten until it strips, then back off a quarter turn.

Moritz
05-10-2019, 10:55 AM
Thanks for the responses, and they confirm my ongoing research. I was clearly twisting too hard. I read somewhere that where torques weren't specified, use no more than "a finger on the spanner". I'll also confirm I'm not bottoming out, and say this because the 1 inch bolts in there, post a rebuild, seemed to be short bolted (only engaging a thread or two). I went to 1 1/4 inch, don't think they are bottoming but will confirm. Finally, I bought a cheap (but good reviews on Amazon) beam torque wrench, hopefully avoiding another visit to the machine shop. Getting to be embarrassing. Thanks