1756cc Torque Specifications

Keep it on topic, it will make it easier to find what you need.
Nut124
Posts: 748
Joined: Wed Oct 25, 2017 6:39 pm
Your car is a: 1978 124 Spider 1800

Re: 1756cc Torque Specifications

Post by Nut124 »

3505jd wrote:Nut124

Big thanks for that information. I will be using a set of new conn rod bolts from Auto-Ricambi.
When you removed the over-torqued bolts, did you observe any bearing damage?
No, no damage. I do not think there is anyway any over torque could cause bearing damage. The bearings do not get any tighter no matter how much you torque the cap bolts, unless the bearings are too thick for the job and there is a gap between the two sides of the rod or main journal. If that were the case, the engine would fail anyway.
3505jd
Posts: 25
Joined: Wed Jun 26, 2019 5:19 pm
Your car is a: 1974 Fiat 124 Spider

Re: 1756cc Torque Specifications

Post by 3505jd »

Based on your information, I will proceed with my engine rebuild with confidence. Can't thank you enough!
Nut124
Posts: 748
Joined: Wed Oct 25, 2017 6:39 pm
Your car is a: 1978 124 Spider 1800

Re: 1756cc Torque Specifications

Post by Nut124 »

3505jd wrote:Based on your information, I will proceed with my engine rebuild with confidence. Can't thank you enough!
I'm glad I could be of some assistance. I have gotten plenty of help from an engine bulders' forum. The key advice was; when in doubt, stop and re-assess, consult experts, sleep on it.

When you torque the main caps, keep feeling how the crank turns. Did you check clearance w plastigauge?

Once the pistons and rods are in, try to assess the short block turning torque. There are some specs for this and I have the numbers from my build.
3505jd
Posts: 25
Joined: Wed Jun 26, 2019 5:19 pm
Your car is a: 1974 Fiat 124 Spider

Re: 1756cc Torque Specifications

Post by 3505jd »

My short block was re-built by a reputable engine builder. Unfortunately, they used the torque specs I provided which proved to be incorrect, so I will only have to replace the rod bolts.
3505jd
Posts: 25
Joined: Wed Jun 26, 2019 5:19 pm
Your car is a: 1974 Fiat 124 Spider

Re: 1756cc Torque Specifications

Post by 3505jd »

I would appreciate the turning specs all the same. Do you have a procedure for that checking the turning torque?
Nut124
Posts: 748
Joined: Wed Oct 25, 2017 6:39 pm
Your car is a: 1978 124 Spider 1800

Re: 1756cc Torque Specifications

Post by Nut124 »

Guy Croft book states that a 2l short block with oiled bores should turn over with 12 ft lbs or less with a torque wrench. The torque is not even, highest when pistons are half way up, down the bore. This should be 12 or under.
3505jd
Posts: 25
Joined: Wed Jun 26, 2019 5:19 pm
Your car is a: 1974 Fiat 124 Spider

Re: 1756cc Torque Specifications

Post by 3505jd »

Are the torque specs wet or dry? I cannot find any reference in any of the three manuals I have.
3505jd
Posts: 25
Joined: Wed Jun 26, 2019 5:19 pm
Your car is a: 1974 Fiat 124 Spider

Re: 1756cc Torque Specifications

Post by 3505jd »

Nut124

Is your engine still holding together with 39 lb-ft rod nut torque?
Nut124
Posts: 748
Joined: Wed Oct 25, 2017 6:39 pm
Your car is a: 1978 124 Spider 1800

Re: 1756cc Torque Specifications

Post by Nut124 »

3505jd wrote:Nut124

Is your engine still holding together with 39 lb-ft rod nut torque?
Yes. Do not torque the skinnier bolt nuts to over 40 lbs.
3505jd
Posts: 25
Joined: Wed Jun 26, 2019 5:19 pm
Your car is a: 1974 Fiat 124 Spider

Re: 1756cc Torque Specifications

Post by 3505jd »

Thanks Nut124
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