Overdrive taking a while to work

[Bradjones7105]

So basically, coming into the colder weather my overdrive is taking a while to kick in, one it does, it flicks on and off every time, I'd say that rules out the switch be faulty, my plan is to drain the oil and check the filter, and refill with new oil obviously, has anyone els experienced this?

[RobPearce]

Cold oil.

You may be right about the filter. If it's a little clogged, the cold, viscous oil won't pass easily and it'll be a bit reluctant. Once it's warmed the oil up a bit, though, it thins out and passes through fine.

[JohnD]

Have you seen Canleys page on O/d troubleshooting?   https://www.canleyclassics.com/?archive=the-d-type-overdrive

 

[RobPearce]

I don't think that page covers Brad's symptoms, unfortunately.

[Pete Lewis]

I would also check the inhibitor switch  , when its playing up hold the gear stick to the left and to the right 

if that has some effect it  shows its the inhibitor needs a little adjustment 

is this on a 2500  so is it J type or A type OD  ????

On J type it can be the solenoid internals need a good clean out , remove the sol remove smal circlip shake out the internal plunger/spool valve and clean it all   this can give the OD a mind of its own 

the easy one is worn out wiring to the gear stick switch

Pete

cant advise on A Types 

Pete

 

[Bradjones7105]

Hi everyone, thakyou for all the feed back, so, I changed the oil, and put a new filter in, and cleaned the flat square gauze filter out, so far so good, been out today and it took about 30 seconds then kicked in which is a massive improvement! So hopefully my problem is solved! Thanks again

[JohnD]

30 seconds?   From switch to overdrive?   That is achingly too long!     O/d should engage in a second or less.

The action depends on oil pressure, driven by an eccentric on the input shaft.     I suggest that you have excess wear there or else in the pump.

See 20,21 et seqq below (From Canley's)   

John

Edited November 24, 2022 by JohnD

[Clive]

11 hours ago, Bradjones7105 said:

Hi everyone, thakyou for all the feed back, so, I changed the oil, and put a new filter in, and cleaned the flat square gauze filter out, so far so good, been out today and it took about 30 seconds then kicked in which is a massive improvement! So hopefully my problem is solved! Thanks again

What sort of road speed? The pump runs on road speed rather than revs. 

But it all sounds slow, as John says it should be almost instant, although a bit slower when cold. But even then, a few seconds, and the oil soon warms.

I am wondering if teh solenoid is sticky? Does it come out of overdrive instantly, or is that too sluggish?