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Tuning issues with BJ8

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John_Progess

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I finally got the BJ8 on the road. I am using new plugs, wires, standard points and everything is rebuilt. I have set the timing using a timing light to about 18 deg BTDC (from an earlier posting here), 600 rpm, and vacuum advance disconnected and it is running on when I shut it off. I am also having a problem getting it to idle using only the slow run adjustment. It is backed out about 6 turns and I have to use the throttle plate screws in about 2 turns for it to idle at 600 rpm. It seems like it will idle down to about 300 rpm so I am not sure about the tach accuracy. Any suggestions will be appreciated. Thanks and have a good day!

John
 
Interesting, the shop manual says 15°BTC. Did you sync the carbs yet?
 
Re set the timing to 15 Deg BTDC as Greg mentioned and the tachs are most likely off 200 Rpm one way or the other. Most likely 200 RPM low. May be set timing at ~ 3000 and let bottom end fall where it may. Check Mixture balance also
 
John, I believe your run-on situation is mostly affected by the advanced timing. As we said earlier that the timing should be about 3/4th of an inch back on the damper from TDC. That is close to 15 degrees. I know when ever I set my BJ7 up with more advance than that, I usually have run-on. My engine would run-on just sometimes even set at 15. Usually heat related on very hot days. Syncing the carbs should entail nothing more than closing both throttle shafts and joining them up. Hopefully nothing is bent. I have always been able to idle my engine on the slow run screws. (by the way we are talking about the HD type carbs ). Usually I could not get the idle slow enough for my liking. Mostly around 800 rpms. The one thing i think that will give you the most head ache when adjusting SUs is if the jet is off alot more than you think. Until you get it close it is hard to tell where it is. So make the jet adjustment exactly as the book tells. then go from there. With the throttles closed, the jet adjusted as the book says, the only other variable is the slow run screws. Oh yeh, and one more thing... the timing. If you retard the timing, you will slow the engine down.
 
Vette,
I have not been able to get the engine to idle with the throttle shaft adjusters backed completely off. While trying, I have been able to temporarily get it to idle down to almost no reading on the tach! Does 6 turns of the slow run adjustment seem ok? I have (I think) set the mixtures with the pin that raises the piston so that the engine does not bog down when the piston is raised slightly and this makes the top of main jets set at .100" below the bridge and both carbs are the same. I will go and change the timing to 15 deg BTDC and give a ride. Thanks for your help. I also have not been able to get the OD to function. I performed the tests as per the manual and Keoke on my previous posting but I will keep working on it. This saturday is our British Field Day and I need to get the Healey ready. Thanks for all your help and have a good day!

John
 
John, re: OD -- If you have confirmed that the solenoid is operating, the next step is to drive the car with the tunnel off (or run it while on jack stands) and press down the operating lever on the passenger side while in 3rd or 4th gear (never in reverse!!). If this engages the overdrive, then you have a solenoid operating lever adjustment issue. If it does not engage the overdrive, you have a hydraulic oil pressure issue.
Let me know which is the case and I can give you further advice.
 
Tim,
After the show this weekend I plan to remove the tunnel which on a BJ8 is no fun! I will let you know what happens. Thanks for the response and have a good day!

John
 
:savewave:
Hey Tim, did you not mean pull uo on the operating lever rather than push down.---Keoke
 
John_Progess said:
Tim,
After the show this weekend I plan to remove the tunnel which on a BJ8 is no fun! I will let you know what happens. Thanks for the response and have a good day!

John
Click to expand...
I had a solenoid go bad with the following symptons.
In static checking it, it was heard to make a loud strong click that would indicate it was working. However, this was a static check and it did not have enough pull down power to actually pull the lever under load(car moving, etc.), and because of this it did not work.
Patrick
 
Keoke said:
:savewave:
Hey Tim, did you not mean pull uo on the operating lever rather than push down.---Keoke
Click to expand...

Keoke, I know you are right most of the time, but on my car, the solenoid pulls up the lever on the driver's side which pushes the lever on the passenger side down. So, if you're engaging the OD on the passenger side, you push it down. The lever on the solenoid side is facing rear, the lever on the passenger side faces front so moves in the opposite direction when the solenoid pulls the lever up. :smile:
 
Patrick67BJ8 said:
John_Progess said:
Tim,
After the show this weekend I plan to remove the tunnel which on a BJ8 is no fun! I will let you know what happens. Thanks for the response and have a good day!

John
Click to expand...
I had a solenoid go bad with the following symptons.
In static checking it, it was heard to make a loud strong click that would indicate it was working. However, this was a static check and it did not have enough pull down power to actually pull the lever under load(car moving, etc.), and because of this it did not work.
Patrick
Click to expand...

With the tunnel cover off and the side plate under the solenoid removed, you can see if the solenoid is actually moving it's full travel. Then you can adjust the lever using the factory procedure. If manually pressing the operating lever on the passenger side engages the OD, but even after adjusting the solenoid lever it doesn't, then replace the solenoid and plunger ($50).
 
Do you know if your tach is accurate? I couldn't get mine to idle for anything. Turned out the tach was off. As these tach die the read higher than actual.
 
OK! you be right I will read better next time--Keoke :laugh:
 
I was concerned about the solonoid having enough pull. The click with the tunnel attached was not very loud! Is there a minimum speed you need to engage the OD? Thanks again and have a good day!

John
 
The first step would be to take off the side plate and watch the movement of the solenoid pulling up the lever when you move the gear shift to the right with the OD switch on and ignition on. If that looks OK, then run the car on the road or on jack stands and push down on the passenger side lever all the way when in 3rd gear.

The OD is engaged when there is enough oil pressure in the OD and the switches are on. In my car it engages a few seconds after I shift into 3rd gear if the OD switch is already on. If the car is on jack stands, you should run it in high gear at about 2,000 rpm with the OD switch off to build up pressure. I'm not sure how long this would be, but I'd guess about 2 minutes. Then push down on the lever on the passenger side of the OD. If it engages, you have a solenoid lever adjustment issue, or a weak solenoid.
 
I know this sounds too easy, but I had a reoccuring problem with the OD in that it wouldn't stay in. Found out it was only the weak battery! The generator finally quit charging altogether, when I replaced the battery and rebuilt the generator all was okay.
 
For us oldsters, the cool-guy of automotive journalists in the '50s and '60s was Henry Manney who once said: "there will always be an England since when the motor is shut off,it will keep on running." As described, run-on is commonplace with most Uk cars of the era, especially when engine has been running hot (which is of course most of the time)independent of carb/timing adjustments. For me it is constant on the '67Etype, rare on '65 Healey. Run on is usually explained as carbon deposits on cylinder head glowing hot and acting as spark plug and thus continuing combustion after electrics shut off--this time on purpose--and as such also called "dieseling." Other Manney saying:"torque is only a figure of speech." Especially relevant to his era when us furrin' car guys tried to defend tiny high revving engines to the hot rod crowd.
Jay Glass
 
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