Sprint manifold+downpipe removal

[Jon Tilson]

If you disconnect the engine mountings both sides you can lift it high enough. You will see if bits of bell housing contact bodywork.

What seems to be stopping it?

These sort of jobs are often quicker if you bite the bullet from the 1st and take the engine and box out in one go. It takes about 3 hours....

Jonners

[tarynus]

I was thinking this could be the solution, i ll try that straight away!
Cant really get the whole thing out i dont have much equipement and doing this in a small garage, plus i m only learning mechanics, this sprint is my very first project and i m learning step by step as go on.
Thanks for the answer i ll let you know how it went!

[tarynus]

Nope, the downpipe is blocked between the steering column and gearbox, and don t think anything is comming out that way i ll have to separatr the downpipe first...

[xvivalve]

Being LHD the steering column is going to cause issues, it must be very tight down there? Can you remove the UJ and flexible coupling to give more room, though I imagine that isn't an easy job either!

[tarynus]

I think i'll try to undo the manifold to downpipe screws, now that the manifold is free to move i probably can get better acces to those 3 screws, i ll find a way to soak them in white vinegar (not sure what its called in english) for a day or two, heat them up and hopefully they ll unscrew themselves

[Jon Tilson]

Plus Gas is pretty good as penetrating lubricant.

You need the right spanner - a 9/16 obstruction wrench.

I did wonder about the access and column on a lhd car.

Jeroen in Holland must have done this and may have some ideas....

Jonners

[tarynus]

Thanks for tip! I ll try that

[tarynus]

I finally went for the tough way out, not easy though!
What do recommend to get the manifold look as good as new?
And do you have any suggestions for some modifications which could make life easier with the manifold and manifold/downpipe screws?

[Jon Tilson]

First you need a new downpipe......

Think we have a decent one if you would like to buy it.

Jeroen may have one that is cheaper to ship though. Postage from the UK may be dear.

You need to use studs (copper plated if possible) and brass nuts with a plain and spring washer on the flange joint and not bolts.

The manifold never looks that good. You can try some high temperature paint. I leave mine natural.

Jonners

[tarynus]

Hi Jon, don t worry i got a sport exhaust and downpipe at rimmers during the winter sale thanks for the offer though.

I found those studs at rimmers originally fitted for 1850, are they ok for the sprint?

By the way there doesnt seem to be a manifold to head bush for the sprint, i got some jointing compound from rimmers with the exhaust fitting kit, do you use that instead?

[Jon Tilson]

The manifold to head is just a metal to metal seal.

You can get a gasket now - they are on ebay. I have never used one on a Sprint and try to get a metal to metal seal whenever possible.

I sometimes have to use gaskets on TR7's and 1850's but they always blow after a couple of years.

I have never had a problem getting the sprint to seal. As long as you have good threads in the head and the bolts rotate freely in the manifold - nice and clean
no rust etc and the joint surfaces are nice and smooth it should seal okay.

Not sure if the 1850 studs are the same thread? Its a unf thread in the manifold originally. I prefer UNC thread on brass nuts.
Again be sure these are all good or use helicoils to repair them. You can use whatever studs work for you if you want to go metric with helicoils? You do need a good quality gasket and the surfaces of the downpipe and manifold need to be dead flat to get a good seal/ I do use a little exhaust paste here.

The other important thing is the pipe support bracket on the gearbox. This needs to be in good coindition as well.

Jonners

[xvivalve]

"Refitting is a reverse procedure to removal"

The threaded holes in cast iron manifolds are helicoiled from new, are they not?

[tarynus]

Hi, thanks for all the information!
I think i'll stick to the original thread if it's still in good shape, i found these studs which are 3/8" UNF/Fx2" here: http://www.namrick.co.uk/acatalog/Home_ ... ds_42.html

Is this the right size? I'm not really comfortable with the imperial system

[Jon Tilson]

Best to measure with a micrometer and convert if you can.

254 mm to the inch.

I think threads are measure on outside diameter?

3/8 sounds a tad large to me.

Jonners

[xvivalve]

254 mm is ten inches Jon!