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Once more for the stupid guy?

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T

Tinster

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Data points: warm engine @ 160* and 65 psi oil,
timing 10* advance

Brand new plugs, sparkling white after 90 miles.
<span style="color: #990000">( I enriched the carbs 1/8 turn as suggested.)</span>

Balanced the carbs with the Unisis tool angled at 45*
I covered the main opening, the rectangular small opening
and the the tiny round hole in the upper left.
Same spot both carbs. Reconnected the throttle shaft
and got the carbs to twitchy 900 rpm warm idle..

Stuck a hose in each carb and heard ???? got me.

Front carb: lifted the piston a wee bit- a brief quickening.
Front carb: lifted the piston 1/4 inch- engine died.

Rear carb : lifted the piston a wee bit -nothing happened
Rear carb: lifted the piston about 3/4" - nothing much changed.

What is my rear carb telling me to adjust?


Here's my N0 6 plug with 90 miles on it - before I enriched
the carb 1/8 turn clockwise last hour.

thanks, d
Lean-plug.jpg
 
Sounds to me like the rear carb isn't flowing any air at all.

Can you turn it's idle speed adjustment in until the idle comes up a bit, and try the "lift the piston" test again?
 
TR3driver said:
Sounds to me like the rear carb isn't flowing any air at all.

Can you turn it's idle speed adjustment in until the idle comes up a bit, and try the "lift the piston" test again?
Click to expand...

Randall - would the Unisys suck up the red ball if no air was flowing?
I put the airbox back on a bit ago and test drove the car up to 70 MPH
and also up to 4000 RPM. Would that be possible with air only enetering
one carb??

There is so much I don't know about these cars.

thanks,

dale
 
Tinster said:
Randall - would the Unisys suck up the red ball if no air was flowing?
Click to expand...
Oops, sorry, I missed that part. No, that should indicate that air was flowing. In which case I have no idea what the problem is.<div class="ubbcode-block"><div class="ubbcode-header">Quote:]
I put the airbox back on a bit ago and test drove the car up to 70 MPH
and also up to 4000 RPM. Would that be possible with air only enetering
one carb??[/QUOTE]No, but having air flow under power is no guarantee that air is flowing at idle.
 
TR3driverNo said:
<span style="color: #660000">Huuummm, maybe that explains my twitchy idle?
Can I do any $$$ engine damage if I drive the car tomorrow
about 40 mile R/T at highway speeds the entire trip?

If I can damage the TR6 car engine, I'll play it safe
and drive my Jeep Wrangler.

d </span>
Click to expand...
 
Tinster said:
[color:#660000]Huuummm, maybe that explains my twitchy idle?
Can I do any $$$ engine damage if I drive the car tomorrow
about 40 mile R/T at highway speeds the entire trip?
Click to expand...
Nah, at least not if that's all that is wrong. I've seen people go for years with the carbs so badly out of balance that the engine idles on only one, and it doesn't damage anything.
 
Dale: If you disconnect the throttle shaft link, and manually operate the rear carb only, will the rpm increse?

Tom
 
Dale, did you mean that you lifted the rear carb 3/4inch, or 1/4 inch like the front carb? 3/4 inch, the car should have died. If not, it may be a little rich, to a lot rich (Not sure, as I have never tried 3/4 inch lift.) If it was 1/4 inch, then the rear carb is OK, and the front is a little lean. At a warm idle, lift the piston up a round 1/16 to 1/8 inch. You are looking for a slight increase in revs. I find strombergs tend a little lean, ( that emission BS you know)so don't be surprised if it dies. The key is to try to get BOTH carbs to behave the same, (If it dies in 7 seconds on the front, then 7 seconds on the rear...) Also,to do a proper "Plug Chop" you should be cruising along, and push the clutch and kill the ignition immediately. DO NOT LOCK THE IGNITION!!!!! We can't get a replacement Dale. Doing it this way will give a better indication of how the plug is behaving under normal operating conditions. However, with sporty new plugs, and ethanol/unleaded, it can be hard to diagnose anything anymore. It looks OK to me though.
 
Here's a photo of the plugs AFTER
I enriched both carbs 1/8 turn.

Now a very slight, pale tan on the ceramics.

d

enrichedMixture.jpg
 
OK, install plugs, close hood for a VERY long time and drive the car. No need to pull plugs anymore. Those sealing washers are pretty well getting crushed as can see.
 
Brosky said:
Those sealing washers are pretty well
getting crushed as can see.
Click to expand...

<span style="color: #000099">How can you tell that??
I can easily purchase new plugs.

d </span>
 
Dale,

It's visually obvious if you look at your nice pictures. The compression washers on spark plugs are not designed to be taken on and off repeatedly. Once, maybe twice and they are completely flattened and you risk having them crack and leak if you keep removing and installing the plugs.

Just put them back in, with some Anit-Sieze on the threads and they'll be fine for this go around.
 
I'm afraid Dale is going to make pulling the plugs part of his 60 mile preventive maintenance routine.
 
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