Chassis twist

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jddevel
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Chassis twist

Post by jddevel » Wed Oct 27, 2021 12:16 pm

When I had the chassis of my TC stripped down using the diagonal measurements shown in "TCs Forever" all appeared within tolerance. To the naked eye all appeared O.K. However things appear to not be the case. Having now installed the engine and gearbox (5 speed conversion with no chassis changes) I am unable to get the starting handle into the "dog". Obviously it slides through the chassis crossmember but is off to the left (as seen from the front of the engine) by approximately 2 cms. It's OK vertically just out horizontally. Any advice or thoughts please?

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Re: Chassis twist

Post by bloodysalmon » Thu Oct 28, 2021 1:55 am

hi, not sure why the question is in the swap meet area of this forum but ... have you checked the positioning of your engine mounts? The brackets the same? they been bashed? holes in the right equal space from chassis to chassis side? Your rubber engine mounts true centrally? ... unlikely to be the chassis itself as other things wont work ... again measure from the x-member hole to side-to-side
Chris Blood - TC2686& TC3615

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jddevel
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Re: Chassis twist

Post by jddevel » Thu Oct 28, 2021 6:29 am

Hi Bloodysalmon, It`s in the wrong location because I`m an idiot :lol: :lol:
Have relocated it to the correct section. However in answer to your thoughts all mounts etc. seem OK. However the one measurement that does show a discrepancy is from the back plate of the offside brake drum to chassis (obviously a fixed point) in relation to the same points on the nearside. There is an approximate 10mm difference which is about what is out with the handle and dog. Having got the engine out again there visually appears to be a "twist " in the chassis in the upward curved area over the front axle. My thoughts are that a previous owner may have "dropped" the front possibly nearside wheel into a deep hole. Going to get a welder familiar with cars to have a look.

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Steve Simmons
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Re: Chassis twist

Post by Steve Simmons » Thu Oct 28, 2021 9:10 am

I've moved the topic to the correct forum for you.

On one of my TC's I found the string method was misleading. I measured it out and everything was within factory tolerance. One of the front irons had a slight twist, and the two of them were a bit too far apart, so I decided to have the frame checked and the irons straightened at a local frame shop. What they found was alarming. The chassis was off in just about every conceivable direction - twist, diamond, bowed in on one side, etc the type and amount of misalignments were essentially canceling each other out when measuring with the string.

I don't know if this is your problem, but might be worth considering. Beyond that, you might be able to manipulate the engine mounting plate and gearbox mounts to straighten it out a bit.
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jddevel
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Re: Chassis twist

Post by jddevel » Thu Oct 28, 2021 10:31 am

Thanks Steve for the advice. First problem where I live is the absence of facilities capable of the work. it will mean moving the chassis halfway across the country. I`m exploring all possibilities. First step to get as many measurements as I can to work with other than those in "TCs Forever"

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Duncan M
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Re: Chassis twist

Post by Duncan M » Thu Oct 28, 2021 3:48 pm

If you have a single area of smooth concrete floor to work from, you might be surprised how much you can accomplish by getting the frame flat to start with.

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Re: Chassis twist

Post by jddevel » Thu Oct 28, 2021 11:27 pm

Must admit this problem is taxing my lateral thinking!!

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Re: Chassis twist

Post by jddevel » Sat Oct 30, 2021 6:17 am

Looks as if the problem has been found. Having studied the front engine mounts which I`d discounted originally as being incorrectly fitted but following a conversation and pictures to Roger Furneaux they do indeed appear to be incorrect. Everything having been discounted will refit to suit. Why they have been ill fitted who knows.

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