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TR6 Carburetors 1975 TR6

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Remove 4 each phillips head cover screws from suction chamber cover


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Be careful with the screws, there actually not Phillps heads unless they have been replaced. These were originally 'pozidrive' as are the screws that hold the diaphragm to the piston. A regular Phillps head screw driver can easily strip the heads. If your careful you'll be all right though.
 
ok I'm at it. First diaphram replaced, recommendation for oil (weight, type)

?
 
There was a thread earlier in the week concerning oil weights. If you read it, you can make a decision based on each individuals preferance.
 
Thanks Doug , replaced both the diaphrams, car idles nicely, but... /ubbthreads/images/graemlins/crazyeyes.gif still no power under load and has a much deaper throatier sound than normal, no back fires or anything, just no power. Only drove it around the block as clearly wasn't right. Any thoughts?
 
Car has no filter on the fuel line, only the one in the pump which looked ok, but didn't take out as gas started to leak out (didn't clamp off fuel line from tank). I listened to both carbs wih a hose and they sound even. I realized when giving them gas from under the hood that the deeper throaty noise is coming from carbs I think??? they don't sound normal when I hit the gas. I'm starting to wonder Doug, about your earlier comments about vacuum hoses? Also seperate but possibly related issue: There is one vacuum capsule on the right side of the destributor and a very small hose attached(poorly)to it. The hose (almost like a wire diameter, matbe is a wire?) goes around the front of the engine and upon inspection, was just hanging there attached to nothing>>> Is this a problem or is there another vacuum hose I can inspect? Any thoughts on what is going on here greatly appreciated. I'm also thinking of doing all the ignition wires and plugs new tomorrow...
 
The thin wire sized hose goes from the distributor retard and/or advance (not sure how the 75 is done) and connects underneath the rear carb with a small rubber 90 degree fitting, not easy to find. If this is not connected you get a vacuum leak which among other things will mess up the idle speed; so first things first get that sorted.
As to where the power is going and the funny noise. I would start by pulling all the spark plugs and checking the colour, whitish means too lean, blackish means too rich, oily end means mechanical wear/problems and dry tan colour is perfect.
This will identify whether one or both carbs mixture is set properly, this should be checked after the engine has been up to operating temp for a while. You need a special tool to adjust the mixture and it can be tricky getting it right.
Assuming you don't have an ignition problem (and the sudden onset of the fault would tend to indicate that), my guess is that you may have a float (fuel) height problem, that could be caused by a number of things.....
Needle valves sticking open or closed
Floats damaged or leaking
Fuel lines/filter plugged
Bad/old gasoline
Float height incorrectly set

I spent a year fooling around with mine before I found that the float bowl fuel height was too high on the front carb and I could not lean it out properly.
 
This morning I removed and replaced the spark plugs, I bought the wires but I haven't replaced yet as the old ones really look ok. The rear three plugs were fouled black, front three normal. (the rear carb was the one with bad diaphram) Also I found the place on the Carb(actually the front carb) for the vacuum hose from distributor. I don't have the elbow reducer to fit from carb to hose... Could I use silicon until I get it or some kind of heat resistant tape? Also when I started the car I had the hose inserted to the tube on the carb. Still not running right. I pulled hose out of carb and placed finger over hole ...it was sucking air...Then turned off car and inspected the tube on carb, was dripping gas...any thoughts as to where to go from here??? Thanks in advance for all contributors.
 
I had a fuel supply problem earlier this year. turned out it was a crimped line. But as a result I was running way lean on my front carb and I am told combustion is hotter when running lean. As a result of that my head gasket between #1 and 2 cylinder was burned and I was loosing compression between the two. This came to light while trying to balance and adjust the carbs. They wouldn't cooperate and a compression check revealed low compression in #1 and 2 cylinders. Pulled the head and there it was. Hope this isn't your problem but a compression check might be in order. Phil
 
Don't think that's it as the rear 3 plugs were black(running rich) and front three were normal, thanks though. I have had crimped fuel line problems in the past. Was a real P.I.T.A. to figure out...when my car was restored, the guy that did it used rubber hose in the fuel line where it had to corner, instead of bending the steel tube. Eventually, the rubber broke down and the suction from the fuel pump would suck the rubber segments closed resulting in no fuel to carbs....
 
Hi Fred.....
Those 3 black plugs indicate a very rich mixture on the associated carb. This is reinforced by the dripping gasoline.
You've either got a faulty needle valve inside the carb or the float height is set incorrectly (too high) which is more likely.
I replaced the needle valve on mine and when I set the float per the spec in the manual it was wrong because the needle valve (from TRF kit) was not standard height as the factory unit.
I ended up by trial and error removing the float bowl in situ (6 screws) and kept bending the float tab till I got it right. Got pretty quick at removing thos screws.
 
is the front carb associated with the rear three plugs? How does one know? Also the gaas was leaking from the tube that is associated with the vacuum hose to the distributor...and that is on the front carb on my car...someone else said earlier it should be on the rear carb??? I'm starting to feel like ripping out hte Strombergs and replacing with Webers......Help!!!!!
 
Fred, I'm not as qualified to answer technical questions as some of the gurus so take this with a grain of salt.
If it's a matter of the rear carb running rich I would think it would be either the jet needs to be adjusted (anticlockwise), the float need to be adjusted, or the needle valve needs to be replaced. I know your frustration, but the Strombergs are quality carbs. I'm thinking about going with a three stromberg setup.
 
The vacuum lines on the '75 should go as follows: The front carb bottom goes to the fuel trap assembly wheich goes to the thermostatic vacuum switch, which goes to the vacuum advance. The top outlet, front carb, gets a "T" that goes to the rear carb, top right side outlet. The other direction from the "T" goes to the second fuel trap assembly which ten goes to the thermostatic vacuum switch. The bottom rear vacuum line goes to a "Y" fitting that branches in one direction to the E.G.R. valve. The othe branch from the "Y" goes the rear carb top back outlet.
If you are looking for originality, you can follow this information. If your carbs do not have these described outlets, try plugging off the existing outlets and see what the results are.
I run the line from the advance to the rear carb on my car as it was from the factory. Yours, should you choose to run it, would go to the front carb. Should you run just that line, you would be best to run a radiator hose straight from the rad to the thermostat housing and eliminate the fuel traps. I would not suggest this if you are in and emissions testing county and are running regular or classic license plates.
 
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