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Nice new idle, but it does not stick

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J

Jerry

Darth Vader
Gold
Offline
Group,
I tighted up the intake and exhaust manifold nuts. I adjusted the timing and carburater seetings. Now the car starts right up and idles at about 550rpm. but as it warms up the idle goes up to about a 1000rpm. Anybody have any new ideas?

thanks

Jerry
BJ8
 
Jerry

Idle should be set when the engine <span style="text-decoration: underline">has</span> warmed up - around 750 RPM ish

:cheers:

Bob
 
Hey Jerry,

You may want to check your SU throttle shaft bushings.

Ken (in Rocklin)
 
And make sure the butterflys are closing all the way when the car is hot. Open the hood when the car is hot and idling high and see if you can close the throttle a bit more by hand. this can indicate either weak return springs or a poorly centered throttle shaft at either the external fitting or the butterfly itself. When things heat up and expand they get worse.
 
Jerry,

What idle RPM are you targeting?

I’ve had my BJ8P1 since new and have never gotten a decent steady idle lower than 900RPM, and most of the time closer to 1000RPM. The factors that may be leading to my idle are: higher than normal compression (head shaved .060 in about 1970), the BJ8 has a more aggressive cam, and I am running a little rich, but, I’ve known many BJ8 owners that seem to match my same high idle RPMs.

Ray (64BJ8P1)
 
I have new springs and sctually added an extra one. I did rebuild the carbs which included a replacement of the throttle shafts. While rebuilding, I thought the shafts closes all the way, but who knows at this point. I will try a mirror to look down the intake.

More fiddling.

PS: I am in Loomis, so we are neighbors!
 
Hey Jerry,

A common failure with high mileage SU carbs is that air will enter the carb at the bushings of the throttle shaft. The amount of air will change due to temperature change, due to the different rates of expansion of the different metals. This would cause a different and varying idle in the car and make balancing the carbs a difficult task.
 
The car starts right up and idles at about 550rpm. but as it warms up the idle goes up to about a 1000rpm. Anybody have any new ideas?

If you are using the car tach for rpm level that is just about what it should do--Fwiw--Keoke
 
Ok, I will quit worrying about it. We just got back from Ironstone car show. If you ever want to go to a nice car show, put this on the list. The entry fee is more than covered by a free bottle of wine, two wine glasses, lunch and you get to see very nice cars of every make.

Ironstone Vineyards is the place. Every September.

Jerry
BJ8
 
Yes, Red over white. We should meet more often. Were you there when the judges went around the Healeys? They spent a lot of time looking at Marty's car, then gave the ribbon to David Cross's car. Of course, all the cars there looked pretty good. I think Roger's BRG, and Len Harnett's blue over white were the only unrestored ones there.

Jerry
 
Roger (Donna actually)is an original owner. Roger has a 100-4. Len had paint about 4 to 5 years ago. My wife liked the car with the 5 foot horns that mooed parked behind us.Hey, guys it was a major concours at a winery. I actually had to send car pictures to get entered as it was the first time for my car there.
One of the big highlights was John Nikas being there with Grace,the cancer car that drove across the US for cancer.People from every where he went signed the car with names of people who had or have cancer. His story will be on several TV specials. Great guy. Great stories. A must!
We went to the Clovis all British car show today and there he was again with Grace. (This is a great show of those in the area. We drove about 250 miles one way for it. Great people and well organized. It combines with a large antique street show so I got brownie points with navi-guesser).
 
I am bringing up this old topic because I found the problem! We had an intake manifold leak. I put a set of headers on this car in the hope of getting the heat back to the rear of the car faster. Well, turns out the new headers were interfering with the bottom edge of the intake manifold. I think it prevented the bottom edge from sealing by about 1/32 of an inch. I pulled the intake off and it had burned through the gasket in three places. I ground off the bottom edge of the intake so there was some clearance, and put everything back together. What a difference! Now it drives like a Healey.
Lesson: When you mix old parts with new parts, check the fit. Even if you bought the parts from a well known English supplier of Healey parts. Now a little more carburator adjustments and I will be ready to race my friends Jensen Interceptor! Well, maybe I can beat him for the first 100 yards! He does have an extra 1000 lbs of weight to get going.

Jerry
BN4
BJ8
TR3A starting soon.

Anybody going to the UBSCC Car show in Woodland this weekend? I am bringing the BN4. Midnight Blue over white
 
tahoe healey said:
Yes. White BJ8 and I saw that Roger with blue over white is signed up too. One of my favorite shows.
Click to expand...
Right you are Rich, one of my favorite shows too. See you there, and if any other BCF members show up, pls come over and say hi. Here's a photo of my car.
Cheers,
Roger
 

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I won't be able to spend much time around my car, but I would love to meet and talk to all of you. I am in charge of the show and will be running!
By the way, I am bringing my BN4 to the show and putting a for sale sign on it. So if you see any interested parties, answer their questions and I will meet up with them at some time.
My wife and I are going to start restoring a Triumph TR3A and having 3 British cars is too much. So we will end up with the BJ8 and TR3A in the end.

Jerry
 
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