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sluggish OD, at first

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nevets

nevets

Jedi Knight
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Took the Healey on the first drive of the season after 4 months of hibernation. All went well except the first few times I flipped the OD toggle nothing happened, then after she warmed up, OD engaged. Thereafter, it worked fine without any hesitation. I've noticed some initial sluggishness on previous occasions too, but his time it was more evident. Any ideas about what might cause this?
 
I have had to warm up the oil first before the OD will shift when the temperature is cold. I believe it is fairly typical and not to worry.
I had similar problems even after warm and solved them by taking off the side plate and cleaning out the sludge around the accumulator, taking the ball valve out of the top of the OD and tapping it in to get a good seat/seal. Basically I tuned up the system using technical tips from Norman Nock at British Car Specialists. I did all the work with the transmission in the car. I use 30 weight oil in the transmission.
 
My BJ8 in HK does this all the time.

It's likely just the OD relay contacts building up a little corrosion while the car sits in during the winter, which is somewhat humid in MA if I'm not mistaken.

If it keeps working after you use it, just keep at it. If it starts getting wonky, it might be worthwhile to take the OD relay apart and file the contacts.
 
TimK, Alan - Thanks for the info. Yes western MA is a bit humid. Sounds like my OD is behaving within the 'normal' range. Still it's good to know what can be done just in case.

TimK, was it necessary to remove the transmission tunnel to access the side plate? And Alan, is the OD relay readily accessible?
 
Yes it was necessary to remove the transmission tunnel to access the side plate.
The relay is on the firewall next to the fuse box and accelerator OD switch. It is readily accessible.
 
Taking a tip from Norman Nock, I installed a 10 amp in-line fuse to the wire going from the relay to the OD solenoid (on the transmission). The factory did not fuse the OD circuit. The in-line fuse is available at auto parts stores. You can install it with a crimp tool and crimp connectors.
 
Don't neglect the throttle kickdown switch. I've had personal experience where the points in there stuck and OD would not engage/disengage. My problem started slowly at first, but progressed enough to the point where it had to be replaced.
 
OH! TimK, I really do not know why a 10 AMP fuse was specified. While the circuit produces a 19 AMP inrush current for Milli Seconds this represents only Milli Jules of energy, not enough to heat a fly. The steady state operation of the circuit consumes less than 2 Amperes. consequently a 5 amp US fuse would be quite adequate.--Keoke
 
Just to follow up Keoke's comment with a real-life experience. I just had to replace the 10 amp fuse with a 15 amp fuse because the 10 amp blew when I installed an aftermarket solenoid (purchased from Healey Surgeons) and shifted into overdrive once. The OD was gone the second time I tried to shift into it. A new 15 amp fuse solved the problem.
 
TimK said:
Taking a tip from Norman Nock, I installed a 10 amp in-line fuse to the wire going from the relay to the OD solenoid (on the transmission). The factory did not fuse the OD circuit. The in-line fuse is available at auto parts stores. You can install it with a crimp tool and crimp connectors.
Click to expand...
I can vouche for this!! I flipped on my OD and smoke poured out of the wires and came rolling from under the dash.
Fuse everything you can! Someone has got to make an fuse block that has more than two fuses that is adaptable to our cars without having to modify the car too much???
Pictures and specs anyone??
Patrick
 
TimK said:
Just to follow up Keoke's comment with a real-life experience. I just had to replace the 10 amp fuse with a 15 amp fuse because the 10 amp blew when I installed an aftermarket solenoid (purchased from Healey Surgeons) and shifted into overdrive once. The OD was gone the second time I tried to shift into it. A new 15 amp fuse solved the problem.

No Tim, you have something in real life amiss in that circuit. Obviously , everyone else that installed the 10 amp fuse including my 5 amp one did not have to update the fuse with a 15 Amp unit. Perhaps if we clarified the type fuse{ 5 AMP Slow Blow} required in that circuit and the solenoid is properly adjusted you can join the masses too. P.S. if you installed an American 10 Amp Fuse it has the equivalent performance of a 20 Amp UK Fuse??---Keoke
Click to expand...
 
 
Hey Patrick,
Victoria British may still carry a 12 circuit fuse block for the Healey. I'm not sure of the dimensions though. It also incorperates a flasher relay. Walking around a junkyard would probably get you one also. Years ago, I made my own from 2 6 circuit blocks from a chain autoparts store. Cut and glued the two together to make 4 always hot and 6 switched circuits. Here's a photo.
 

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I may have something amiss, because the original solenoid failed. However, it failed without blowing the 10 amp fuse. There were no signs or symptoms. I had done a lot of work cleaning up the OD hydraulics and checking the adjustment of the lever actuated by the solenoid. Maybe I increased the load on the solenoid, but I don't know how I did. The new one works fine for now, with the 15amp fuse. The fuses are Buss mini standard (not slow blow) AGC fuses in an in-line fuse holder. I suppose if I lose the new solenoid I'll have to get to the root of the problem.
 
Hi Tim, What is being said here is, this type circuit requires a Slow Blow type fuse. Using a standard, fast blow , fuse can cause the circuit to be over protected.--Keoke
 
Thanks, Keoke, Now I have to find such a fuse to go with the holder I installed, or go to a different type holder
 
Fuse blocks are readily available at boating parts stores. For those using an inline fuse, where exactly are you locating it? Anywhere in the wire leading to the solenoid?
 
I put mine connecting to the C2 terminal of the overdrive Relay then connecting to the wire leading to the Overdrive solenoid (white wire). It is just hanging there, so those of you who are neatniks probably would put it elsewhere. I wanted to be able to see the fuse and change it if necessary -- as it was. If you put it under the tunnel, you can't see if it is blown and would have to take the tunnel off.
 
I don't see need for an inline fuse on a BJ8. The overdrive relay is connected directly to the 35 A fuse in the fuse block terminal 3. Am I missing something? please explain.
 
Yep a burned up OD Harness CUZ you have about 25 AMPs too many--Keoke-
 
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