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Triumph TR6 - Vacuum/EGR
|I'm on page 103 of the the blue TRF book and see that I've got problems. My distributor vacuum tube is attached to the rear carb. The EGR valve on my car was removed by the PO. The vacuum tube on the bottom of the front carb is not attached to anything. The car currently has only one flame trap, attched between the distributor and the rear carb.|
I have a second set of carbs I'm rebuilding (with a TRF carb rebuilding kit) I've been to to Buckeye site, have the TRF carb rebuild instrutions, my big Bentley book and whatever information I've plucked from the web. I should note that with my current setup, I average about 10 mpg, and unless I have the chock out one quarter, I backfire.
Here come the questions:
Should I re-intall the EGR valve to bring everything back to "normal" when I put the rebuilts on,
Is there a vacuum option out there that would allow me not to re-install the EGR valve, it can't be right to have a vacuum attachment wide open to nature on the front carb,
I do get after-run, is this related to this mess,
The air pump, and it's associated plumbing and hardware are removed; it sounds like this is common, should I be concerned,
How do I stablize this mess to begin to tune tune the new carbs, when I put them on?
Sorry that this may be involved, but I do have alot of hair left to pull (unllike others, I read)
The air pump and the
What year is your car?
Vac to atmosphere is not good plug with Vac. cap little rubber covers from any car parts place come in most sizes. Try to get a reasonable quality. Put a zip tye on them to keep in place.
As for EGR. All of the emission stuff was done to qualify mostly California. No it did not work real well new. Lose it if you can. Does your state require emission tests for older vehicles. If they do you may have to put it all back on. But if they don't keep it off. and just block everything.
The run on can be caused by a lot of things. Timing, Carbs, excess carbon buildup, vac port wide open. The newer TRs had an anti run on valve under the carbon cannister is all that stuff still there?
By the routing on page 103 and I don't know newer trs emissions that well. But I believe the vac retard to Distributer should be coming from the front carb not back if they are on idle, off idle ports they will screw you up? Most egr are off idle the back one by the routing. Thats going by American. That puts your idle timing off no vac retard. Might cause run on? Likely. Change that to front and block back. You will probably have to retime if on/off ports. Off idle low to none at idle. On idle the reverse. Check I don't know.
As for hair left to pull by the sounds of your E-mail. I would suggest a large bottle of ROAGAINE HAIR RESTORER and a willing partner to rub it in. Well as far as the rub it in part just keep posting and reading this BBS most of the guys are more than willing to rub it in. I understand if caught at early stages like thrust bearings your blockhead can be saved.(:
Let us know
It sounds like you have a late TR (75 or 76?) since you have the air pump?
I am not sure what the difference between the top vacuum on the rear carb and the bottom on the front, but I would definitely move the distributor vacuum to the bottom front, and plug all the unused vacuum ports as Bill suggests. Vacuum leaks have been the bane of my TR experience, but I have just learned to look for leaks if things seem off now. You can get some good rubber ones at almost any decent car parts store with all the emmissions bs.
All the EGR does is recycle gas fumes so they can be burnt. I think the trade offs are better gas mileage with it, but less power since you are mixing in partially burnt air into your combustion chambers. I put mine back on since I found a good one Ebay for $50, but since you have most of the emissions BS removed already, I would probably leave it that way since the car will be easier to tune/diagnose and should have more power. Other than for show, I can not think of any good reason to keep the stuff on.
Before rebuidling the carbs, I would probably make sure everything else is working well before tackling the carbs. I.e. do a major tune and replace the rotor, cap, fuel filter, air filters, and anything else that looks iffy like your plugs. Just doing this stuff, my mileage jumped from 10 to 12-13 mpg.
I rebuilt my carbs last spring. I also used the 3 carb overhaul writeups from buckeye. After doing this, my mileage jumped up to around 15 mpg of city, and 27 mpg highway driving.
The only really tough part of the carb rebuild that I found was reseating the lock washer on the mixture needle. I must have stressed one out when I installed it since the car ran great for a week, then started doing weird things. This is a $0.10 piece that probably caused 2 days of hair loss.
Personally, I am going for the Yul Bryner look (bald/shaven).
This thread was discussed between 10/10/2002 and 14/10/2002
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