BJ8: 650 RPM steady Idle at 45 Degree advance???

[RAC68]

Hi All,

Today, I helped a friend install a new Pertronix negative ground ignition, coil, rotor, and cap in his 1967 BJ8 P2.

Prior to installation, the idle was amazingly low and steady for a BJ8, plugs were a nice dark tan color, it stared promptly when cold with some choke and the acceleration was even and steady. All this from 2 year old pitted points in a distributor that had rust under the rotor, and a misfiring cylinder with a broken boot.

Checking the timing prior to points replacement, I was shocked when touching the engine from the bad sparkplug wire and found timing set to around 45 degrees. This reading was questionable as it was not steady, even with the vacuum advance disconnected.

The 15 minute job of replacing the points with the Pertronix and installing a new coil took close to 8 hours and required the extraction of the distributor as the points would not release from the post. Although the distributor bearings seemed to have no perceivable play, it was quite apparent that this distributor was not maintained regularly by its general appearance and rust under the rotor.

After installation, the car started right up and assumed an expected rough idle before the timing was reset. After fixing the leaking sparkplug wire, timing was now steady but the car would run extremely rough or not at all when approaching the standard 12-15 degree advance but would settle back to a its steady 650 degrees idle when returned to its pre-alteration 45 degree setting.

Was the notch on the pulley in the correct position? When applying white paint on the notch and pointer, only one notch was found. Although the engine was previously rebuilt and the mechanic/owner is now in jail, could he have done something to this car that allows it to get the best and lowest BJ8 idle I have every experienced (I have a hard time keeping my BJ8 lower then 1000 RPM). I would appreciate any thoughts.

Forgot to mention, acceleration is strong, quick, and consistent.

Ray (64BJ8P1)

 

[LarryK]

Check out about modified engine in Triumph. I suggested calling Petronix for their free information. Also suggested installing good carbon wires as a friend had this problem on an old Jag. Seems everyone buys the coil and points, but not the wires. Cured the Triumph and Jag problems.

 

[steveg]

Hi All,

Today, I helped a friend install a new Pertronix negative ground ignition, coil, rotor, and cap in his 1967 BJ8 P2.

Prior to installation, the idle was amazingly low and steady for a BJ8, plugs were a nice dark tan color, it stared promptly when cold with some choke and the acceleration was even and steady. All this from 2 year old pitted points in a distributor that had rust under the rotor, and a misfiring cylinder with a broken boot.

Checking the timing prior to points replacement, I was shocked when touching the engine from the bad sparkplug wire and found timing set to around 45 degrees. This reading was questionable as it was not steady, even with the vacuum advance disconnected.

The 15 minute job of replacing the points with the Pertronix and installing a new coil took close to 8 hours and required the extraction of the distributor as the points would not release from the post. Although the distributor bearings seemed to have no perceivable play, it was quite apparent that this distributor was not maintained regularly by its general appearance and rust under the rotor.

After installation, the car started right up and assumed an expected rough idle before the timing was reset. After fixing the leaking sparkplug wire, timing was now steady but the car would run extremely rough or not at all when approaching the standard 12-15 degree advance but would settle back to a its steady 650 degrees idle when returned to its pre-alteration 45 degree setting.

Was the notch on the pulley in the correct position? When applying white paint on the notch and pointer, only one notch was found. Although the engine was previously rebuilt and the mechanic/owner is now in jail, could he have done something to this car that allows it to get the best and lowest BJ8 idle I have every experienced (I have a hard time keeping my BJ8 lower then 1000 RPM). I would appreciate any thoughts.

Forgot to mention, acceleration is strong, quick, and consistent.

Ray (64BJ8P1)

The notch is TDC on #1. There's a lot of info here in old threads about the measurements for marking the pulley for dynamic timing. Also see Norm Nock's book. Sounds like the distributor needs an overhaul before you worry too much about the timing.

 

[Lotuswins]

Hi Ray, I think you are spot on about TDC being off. Have you a piston stop (old spark plug tapped out with bolt inserted) to verify it is TDC on the mark? If its 45 degrees off, perhaps you can eyeball when the piston is very close to TDC, and check the mark.....

 

[andrewss]

Either the original TDC marks are completely wrong or the weights/springs in the dizzy are so badly clogged that they are static... Strip down the dizzy, clean, oil and then re-check the TDC.. 45 degrees is not correct !!

 

[DerekJ]

650 revs isn't particularly that unusual. My car idled at that when it had Twin HD8s.

 

[andrewss]

650 revs isn't particularly that unusual. My car idled at that when it had Twin HD8s.

Agree that 650 is great and not unusual but not at 45 degrees ...

 

[RAC68]

Hi All and thanks for your input.

I received a call from the owner of the Healey this morning and he tells me he took a 2 hour drive on highway and local roads through the NJ shore towns to test the new ignition. His Healey is running strong, smooth, and steady and indicates the acceleration is tremendous. “Thanks Ray and I definitely owe you. In the 40 years I’ve owned the car, I have never loved and enjoyed my Healey more. I love this car.” Although I would like to correct what ever is wrong, the bar is now set too high to risk a friendship if I diminish performance in any way. Again, thanks for your ideas but I think I am going to leave well enough alone for now.

When helping, I have learned through experience that you can make suggestions and even direct to an extent, however, anything more and it becomes your problem and responsibility. However, when the time is right, I intend to find a way to pull and dismantle the distributor for examination to see if it is clean and performing properly. I also intend to check the TDC timing mark for correct positioning with respect to #1 cylinder, hopefully a lot sooner, as no operational changes are necessary.

Also, to clarify, when trying to time the car, I can see that the mechanical advance does work, as does the vacuum advance when hooked up. I am using an adjustable timing light and roughly validated its accuracy by checking the timing on my Healey which has a Crane electronic ignition and is set to 17 degrees. The reading was dead on so I must assume the 45 degree reading is close if not correct.

Thanks again and all the best,
Ray (64BJ8P1)

 

[John Turney]

Sounds like "If it ain't broke, don't fix it."

Although it appears something is wrong, the ultimate test is how the car runs.

 

[GregW]

I would try a plain old inductive timing light. Sometimes the more advanced lights don't like electronic ignitions, especially the multi-spark kind. It may be that nothing is wrong, just the light you're using is incompatible.

 

[DerekJ]

I do not believe the car would idle at a 45 degree advance. It cannot be correct.

 

[Bob_Spidell]

Have heard--hasn't happened to me--that the outer part of the crankshaft damper (aka harmonic balancer) can slip when the rubber part gets old and hard:

https://en.wikipedia.org/wiki/Harmonic_balancer

This would give an erroneous timing reading. Given the age of our Healeys it's probably a good idea to have the damper/balancer rebuilt on principle (I had a balancer fail catastrophically on a '96 Cherokee I once owned).

 

[steveg]

Have heard--hasn't happened to me--that the outer part of the crankshaft damper (aka harmonic balancer) can slip when the rubber part gets old and hard:

https://en.wikipedia.org/wiki/Harmonic_balancer

This would give an erroneous timing reading. Given the age of our Healeys it's probably a good idea to have the damper/balancer rebuilt on principle (I had a balancer fail catastrophically on a '96 Cherokee I once owned).

Bob, the above damper issue wouldn't affect the timing. I recently had my damper rebuilt and it unbolts from the front of the pulley - the pulley is keyed to the crankshaft. The damper is not in any way indexed to the crank.

The car above was originally stated to have a bunch of rust and other grunge inside the distributor - IMO the issue is most likely there.

 

[Bob_Spidell]

Aren't the damper and pulley one piece? https://www.damperdudes.net//product_info.php?cPath=34&products_id=244

IIRC, the timing mark on my BJ8 is a groove on the outer ring of the damper; if the outer ring moves WRT the inner, the timing indication would be off. Or am I missing something (It's late and I'm tired ... not thinking too well).

 

[steveg]

Aren't the damper and pulley one piece? https://www.damperdudes.net//product_info.php?cPath=34&products_id=244

Just askin' ... It's late and I'm tired ... not thinking too well.

Nope.

 

[Bob_Spidell]

The ones on the later BJ8s are one piece (part# 35 on the same Moss diagram). That's the one I'm familiar with.

 

[steveg]

The ones on the later BJ8s are one piece (part# 35 on the same Moss diagram). That's the one I'm familiar with.

That's interesting, I stand corrected.

But is the design such that the TDC notch is not permanently indexed to a position on the crankshaft, per the earlier design?

 

[Bob_Spidell]

Working from memory (had it off a couple years ago): Pulley and balancer are one piece; keyed to the crankshaft. The timing mark is a crosswise groove on the perimeter of the outer ring of the balancer; if the outer ring slips WRT the inner disc of the balancer the timing indication would be off. I've seen a balancer come apart; it ain't pretty.

 

[RAC68]

Hi All,

As far as I am aware, the notch is located on the inside edge of the pulley which is keyed to the crankcase. If the damper has broken loose and moved, it should not affect the position of the pulley. I also looked at my BJ8P1 damper and could not tell, but don't believe my damper was integrated. However, my reading of the Moss description for the integrated damper and pulley is that models prior to the designated BJ& forward were different from former BJ8s and models. As such, and since separate dampers are no longer available, they suggest everyone install the integrated version. However, integrated or not, I would expect the pulley would be still anchored to the crank with a key and the damper vulcanized to the pulley. If the damper moves, on either model, integrated or non, there should be no movement in the pulley or TDC notch.

Greg may be correct that my adjustable timing light may be having difficulty with the Pertronix and high powered coil. I don't think this is the case as I have checked my BJ8 (Crane Electronic Ignition, 40KV Pertronix Coil) and registered a steady 15 degrees without vacuum advance and could easily see the effect of both distributor and vacuum advances.

Until I do get a chance to tactfully check to make sure the mark I used was correct and not another notch placed for another previous reason, I tend to believe this is the case.

Again, thanks all,
Ray (64B J8P1)

 

[Keoke]

I would try a plain old inductive timing light. Sometimes the more advanced lights don't like electronic ignitions, especially the multi-spark kind. It may be that nothing is wrong, just the light you're using is incompatible.