How do I replace the rear cross tube on my chassis?

[Devs]

I need to replace the cross tube on the chassis of my TR2 (as per piccy attached)

 

I've purchased the replacement item from Moss, which is considerably longer then the original. My question is this:

 

Do I just cut the new part down to size and then simply replace the 'inner' section by butting it up to the chassis rails, or as the original item extends all the way through the chassis, do I cut the original away (on all sides of the chassis) & then attempt to thread it through the original holes and then weld it up again?

 

I'm not wording this very well so to simplify: How do I replace the rear cross tube?

 

Many thanks!

 

[david ferry]

Devs,

 

The question has to be around what else you may be doing to the chassis/tub/car.

 

Is this the only problem, or are there others that need to be sorted out?

 

Are you looking for a short term fix, or a proper job?

 

A sad statement but I suspect you will find more needing to be done, if you go looking for it.

 

What are the rear, rear spring mounts like? If they are in a similar condition and 'thin', you must also replace that tube.

 

I suspect that the lid is heading off the can of worms.

 

Sorry for the gloomy view.

 

Regards

 

David

[Devs]

Thanks for your reply David, but to be honest, the rest isn''t too bad. I've had the wire brush all over it & attempted to get through it with a screwdriver, but it's solid.

 

The tub is currently off the car, so I can get to everything quite happily, but want to do the job correctly. I've also got the other tube (I purchased the wrong one initially due to a numbering problem in Moss' earlier catalogue) so I may as well replace that one too.

 

I've got a mobile shot-blaster coming round this weekend to blast a couple of panels, so I'll ask him to clean up the rear end for me so I can have a good look at what's left before I count my chickens.

 

If you grind off the welds at either end (not that you can get to them very well - will it just fall out?

[BrianC]

I'm relieved to see that you also plan to replace the other tube as this is crucial to the suspension on the live axle cars as it serves as part of the rear spring hanger.

 

The rust on my first TR3A was nowhere near as bad as yours appears and I had no reason to suspect problems. However, one day on a fast right-hand bend, the car decided to steer itself from the rear-end. Result was a lengthy off-road excursion across the grass and violent side-impact into a concrete fence post. Fortunately no-one was injured and the car was still driveable, although steering on the twisty country roads was interesting to say the least

 

When we got home, it was found that the right-hand spring hanger had pulled out of the chassis. Whether this was the cause of the problem, or a result of the impact is not absolutely certain, but almost certainly the former. Several years later, when buying some parts from an ex-TR owner locally, I mentioned the accident and it turned out that he had owned the car many years before and had had that rear spring hanger welded-up

 

All of which, is a long-winded way of saying that simply welding the tubes on is not sufficient. Whenever I have had welding done in this area on my other TRs I have ensured that the tubes have been reinforced internally and that the side sections of the chassis through which they pass are replaced or reinforced.

 

(BTW - this is the car which 'currently reduced to CKD form' in my signature - but the chassis is now deceased!)

Edited October 23, 2007 by BrianC

[stuart]

Devs it may be an idea and I suspect when then rear of the chassis is blasted you may opt for, the complete rear section of the chassis to be replaced as this is available already made up as one piece. Moss part number CHAS8. This is a lot easier to replace than trying to remove and refit the tubes.

Stuart.

[Devs]

Thanks for the info guys. I did originally consider the replacement chassis section, but I'll take a good look at what I find after the weekend. and give it serious consideration.

 

I've also read in some of the restoration books that it's common to reinforce the cross tubes with some solid metal rods - now I can see why!