1989 740-GL CPM/Crank Position Indicator -removal issue

[RiverMechanic]

Hi.
New to the forums, new to this model and most volvos in general, but experienced as a mechanic.

I've got a 740-GL wagon here I'm working on for a friend (for free). Looks like we need to replace the rpm relay/crank position indicator. The car was parked too long uncovered and got water into the sensor. I've got the 10mm bolt out BUT the sensor/relay is frozen in the hole.

I've not broken the mount for it (yet). I've applied as much force to try and turn or get it out of the bell housing/mounting bracket as I fell comfortable with doing -I.E. jimmied it with a flat-head and then tapped it with a long flat bar and mallet trying to try and get it to turn/rotate. This has only resulting in part of the CPI tang/bracket on the relay ITSELF chipping off (the piece didn't fall into the bell housing at least) -the relay is really siezed up in there apparently! The engine/tranny is still in the car.

Question:
When you have a frozen relay in this difficult to access location, short of dropping/removing the tranny to access it, is there any other techniques anyone has done that we could try? I read that the water invasion leads the magnets in the CPI to rust and swell, locking the relay into the mounting brace by the flywheel. That mounting bracket, from what I see, it attached by two 10mm bolts. From what I've read there's a very close tolerance (0.030 inch clearance) needed for the relay to the flywheel, which I'm guessing needs to be restored for the relay to function correctly. So removing the relay mounting bracket would mean -unless we luck out gambling on it- we'd have to drop the tranny to get the clearance correct once we replace the CPI/RPM if we remove the whole mounting itself, CPI included.

Any advice on removing a stuck CPI/RPM relay?

p.s. Why didn't they stick this thing on the passenger side of the block looking at the flywheel that way? Argh!

[93Regina]

740-GL wagon

Maybe water over the dam, but Volvo used a Radio Suppression Relay, which sends 12 volts to fuel injectors. But, it is turned on via Fuel Injection Relay...which means engine must be turning over, or key-switch is turned on, then for a few seconds, both relays are fired up. LH 2.4 setup.

I've not had an issue with removing CPS on 240/940s.



So, normally, one does the following

1. Check for injector pulse or voltage at injector with engine rotating.

2. Test resistance of CPS: 180 ohms + or - 10%.

2. Check voltage output of the CPS: AC voltage output during cranking is 0.5 V.

I've taken them out on passenger side...

Do what you have to do to get it out...WD-40...etc.

[lummert]

Can it be removed mounting bracket and all?