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Voda2000 Avatar
Voda2000 Andrew McMillan
Winnipeg, MB, Canada   CAN
Well I got the shafts out of both carbs and the shafts are visably worn but the bushings are fine. I check the bushings using the part of the shaft that was outside the carb so there was no ware on it and it's tight in the bushing.

The shafts are thoast and the butterflies are a mess. Someone if a very poor job of trying to solder the anti run on valves closed. So those are on the shopping list.

Regarding the jets how do I tell if they need to be replaced? If theses are good I'll going to modify them with the two penny trick.

Also I have not removed the main jet bearing from the carb body. Do I need to check it for ware and if so what and I looking for?

I also broke Carter's second instruction and dropped the suction chamber. Fortunately it didn't fall to far and seems ok. There was a very slight nick on the edge but it shouldn't effect operations.

Thanks for all the information in reaming the bushings. There is some really good information here.

Andrew



1978 Triumph Spitfire

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Tonyfixit Avatar
Tonyfixit Tony M
Duncan, BC, Canada   CAN
My rule of thumb is to look at the needle (assuming it is the original ) the needle has a bias, you will see a shiny wear line on one side, if the needle wears, the jet wears. If the wear line is any more than about 1/32" wide, I would consider replacing the jet. But needle wear is more critical than jet.

What type of butterfly do you want? You can buy plain disks, or do you want those poppet valves.


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Voda2000 Avatar
Voda2000 Andrew McMillan
Winnipeg, MB, Canada   CAN
Thanks Tony.

I don't want the poppet valves, I just want plain. It's interesting to see the two "anti-stall" styles, I'm cuerious what the point of those are. Seems like it would just increase idle speed.

I'll check the ware in needle. They are ABT needles and appear to be original. These will be going on a mild performance motor eventually so I the needle choice hasn't been confirmed. I think I'll hold off changing the jets until I am replacing the needles.



1978 Triumph Spitfire

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carChips Avatar
carChips Victor Harnish
Kelowna, BC, Canada   CAN
1933 MG Magnette
1973 Triumph Spitfire 1500 "Chip"
1989 GMC Sierra 1500 "Bush Truck"
Those needles won't be right for your altitude anyway, you'll need a slightly leaner needle.



'S all for now
Vic

Tonyfixit Avatar
Tonyfixit Tony M
Duncan, BC, Canada   CAN
In reply to # 1511434 by Voda2000 Thanks Tony.

I don't want the poppet valves, I just want plain. It's interesting to see the two "anti-stall" styles, I'm cuerious what the point of those are. Seems like it would just increase idle speed.


A good write up here from a Volvo site
http://www.sw-em.com/SU_Carb_Throttle_Plate_Early_vs_Late.htm

clshore Carter Shore
Beverly Hills, FL, USA   USA
In reply to # 1511283 by Voda2000 ...
I also broke Carter's second instruction and dropped the suction chamber. Fortunately it didn't fall to far and seems ok. There was a very slight nick on the edge but it shouldn't effect operations.
...

You must ensure that the suction chamber bore has not been distorted by the impact.
Just fit the piston back in and run it up and down, feeling for any binding or tightness.
If there is none, then you are good, else there's an issue to deal with.

You can spray or paint some dykem blue inside the bore, and run the piston up and down.
Then examine the bore to see the witness mark where the binding occurs.
Use a bit of fine crocus cloth, or white polishing compound on a cloth to carefully
dress the ONLY the high spot, until the piston just clears without binding.
Take care not to get any abrasive into the damper.
Flush and clean the chamber and piston very thoroughly before returning to service.

Voda2000 Avatar
Voda2000 Andrew McMillan
Winnipeg, MB, Canada   CAN
Hi Tony,

That is an interesting read. I'm not sure I totally agree with the author that the poppet value doesn't interfere with the air flow. It really occupies a lot of space in there.

Hi Carter,

I checked an it runs up and down with no binding. It fortunately fell only a few inches on to a wooden work surface. The only issues was the edge caught the intake manifold that was sitting there and put the tiniest burr right on the edge which would not allow the piston to be installed. I just pushed and the burr came off. I did nearly have heart failure.

Hi Victor,

I thought ABT were a factory needle for a 1500 and I'm only at about 700ft above sea so I thought there would be close for a stock motor.

I'm planning on rebuilding the motor to a 9:1 compression, Mk III cam, rould airfilters (not stock box) and a 4 into 1 header (someday a 4-2-1 but I have have the 4-1 in the car and its cost savings). Any suggestion in needle?

Thanks,

Andrew



1978 Triumph Spitfire

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Voda2000 Avatar
Voda2000 Andrew McMillan
Winnipeg, MB, Canada   CAN
Also, when I was disconnecting the jet from the float the hose pulled out of the brass piece. I’m assuming that means the jet is toast?



1978 Triumph Spitfire

clshore Carter Shore
Beverly Hills, FL, USA   USA
In reply to # 1511498 by Voda2000 Also, when I was disconnecting the jet from the float the hose pulled out of the brass piece. I’m assuming that means the jet is toast?

It's just a 'simple' crimp, there is virtually no fuel pressure (maybe 0.5 psi), since it's just a gravity feed from the bowl.
But it's in a place where you absolutely do not want a leak, and the crimp must be perfect.
So yes, new jets are recommended in that case.

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Voda2000 Avatar
Voda2000 Andrew McMillan
Winnipeg, MB, Canada   CAN
In reply to # 1511504 by clshore
It's just a 'simple' crimp, there is virtually no fuel pressure (maybe 0.5 psi), since it's just a gravity feed from the bowl.
But it's in a place where you absolutely do not want a leak, and the crimp must be perfect.
So yes, new jets are recommended in that case.

Makes sense. Thanks.



1978 Triumph Spitfire

carChips Avatar
carChips Victor Harnish
Kelowna, BC, Canada   CAN
1933 MG Magnette
1973 Triumph Spitfire 1500 "Chip"
1989 GMC Sierra 1500 "Bush Truck"
Converting to standard jets is easy enough.



'S all for now
Vic

Voda2000 Avatar
Voda2000 Andrew McMillan
Winnipeg, MB, Canada   CAN
Finally finished cleaning them up. Overall looks pretty good. I talked to Burlen and they didn’t have a kit but provide me the parts list that will “convert” the carbs to run standard jets and solid disks along with a full rebuild.

The only parts that I found were missing was a lock washer for the float bowl cover and one of the float vent baffle/cover pieces. The latter I can’t find on on Burlen’s site.

The disappointing thing was finding a hole in the heater pipe on the manifold. Since it’s on the vertical piece of the tee I’m thinking about just cutting it off as it didn’t match the plumbing on my North America spec car anyways.

The needles are ABT which will probably not be correct for this motor when done but I’ve got to sort that out. The other thing I was wondering is do the springs need to be replaced? And if so do most people run the Red spring?



1978 Triumph Spitfire


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carChips Avatar
carChips Victor Harnish
Kelowna, BC, Canada   CAN
1933 MG Magnette
1973 Triumph Spitfire 1500 "Chip"
1989 GMC Sierra 1500 "Bush Truck"
These is the little kit you need. https://rimmerbros.com/Item--i-GRID005599



'S all for now
Vic

Voda2000 Avatar
Voda2000 Andrew McMillan
Winnipeg, MB, Canada   CAN
In reply to # 1512874 by carChips These is the little kit you need. https://rimmerbros.com/Item--i-GRID005599

Thanks. I think that’s part of what Burlen suggested but they also gave me the P/Ns for other parts I’ll need for rebuilding.



1978 Triumph Spitfire

carChips Avatar
carChips Victor Harnish
Kelowna, BC, Canada   CAN
1933 MG Magnette
1973 Triumph Spitfire 1500 "Chip"
1989 GMC Sierra 1500 "Bush Truck"
That kit works very well and easy ti install, I just did a friends carbs with it, easy peasy.



'S all for now
Vic

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