Distributor spin on itself

[Mtl-Diesel]

Hey folks. 1984 Mercruiser 140. Put the boat in the water today. Went to start it and it would not start well. Started very rough like it was running on three. Stalled. Would not start again. Opened the doghouse and discovered when I turn the key, the entire distributor assemble spins. Ripped all the wires out. Not happy.

Any idea what would cause this? I checked the nut that holds the collar down and it was tight. I'm perplexed.

 

[GA_Boater]

Is the distributor body turning or the cap?

 

[Mtl-Diesel]

Is the distributor body turning or the cap?

It's the entire assembly.

 

[GA_Boater]

Has the distributor ever been removed? Is the clamp on right side up?

 

[Mtl-Diesel]

Has the distributor ever been removed? Is the clamp on right side up?

It has not been removed until today when I had the problem. Inspected it to see if it had damage, missing teeth. All looks good as does where it meets up with the gears in the block. Clamp was on correctly. Slightly bowed upwards.

 

[Scott Danforth]

if it was clamped, it couldnt move

either the housing is broken allowing the top half to sping, or the bushings seized and the clamp wasnt tight.

 

[Mtl-Diesel]

if it was clamped, it couldnt move

either the housing is broken allowing the top half to sping, or the bushings seized and the clamp wasnt tight.

Ok. I looked carefully at the distributor again. It looks fine. Everything spins that should. Nothing appears seized. Is it possible through vibration the bolt loosened enough to allow it to spin under pressure but still feel tight as I removed it? Just throwing S*&# at the wall....

 

[GA_Boater]

Clamp was on correctly. Slightly bowed upwards.

Should be bowed down if anything. An example;

 

[Scott Danforth]

lets put this another way, there should not be enough resistance to the internal bushings to allow the distributor to spin with the clamp removed. turn slightly.... yes, however not enough to spin it

take the distributor out, pull it apart (drive the pin out of the gear), put two new bushings in the distributor (Napa has them).

 

[Mtl-Diesel]

lets put this another way, there should not be enough resistance to the internal bushings to allow the distributor to spin with the clamp removed. turn slightly.... yes, however not enough to spin it

take the distributor out, pull it apart (drive the pin out of the gear), put two new bushings in the distributor (Napa has them).

OK. I hear what you are saying. I will do that this evening when I get home. How do I determine what part number for the bushings I need? I am guessing this will solve my issue? When unit is placed into block without the collar, I can very easily spin it around. Almost like a top.

 

[Scott Danforth]

dont know part numbers, measure the distributor shaft, should be 0.500, however need to verify. go to Napa, tell them you need distributor shaft bushings for X.XXX dimension shaft. the parts guy will go back and pull them from the bin.

if the Napa still has a machine shop, then they will most likely have a price for the labor to install as well.

However if the guy says he needs a year make and model, then ask the old guy behind the counter.

 

[Mtl-Diesel]

dont know part numbers, measure the distributor shaft, should be 0.500, however need to verify. go to Napa, tell them you need distributor shaft bushings for X.XXX dimension shaft. the parts guy will go back and pull them from the bin.

if the Napa still has a machine shop, then they will most likely have a price for the labor to install as well.

However if the guy says he needs a year make and model, then ask the old guy behind the counter.

So to confirm, when distributor is installed in the block without the collar, I should be able to turn it with some resistance. But if I can spin it freely without resistance, then the bushings are shot?

OK. Any idea what I should be looking at for cost? Want to make sure I don't get hosed.

 

[kenny nunez]

Just a question, have you removed the plate that mounts the points? If the pins that mount the fly weights came loose that could cause the distributor to rotate.

 

[Mtl-Diesel]

Just a question, have you removed the plate that mounts the points? If the pins that mount the fly weights came loose that could cause the distributor to rotate.

No I have not. I have not removed the cap to be honest. I guess I should look. I assumed all was fine in there since the entire unit was spinning.

 

[Bt Doctur]

So to confirm, when distributor is installed in the block without the collar, I should be able to turn it with some resistance. But if I can spin it freely without resistance, then the bushings are shot?

When a dist is installed in a block is does NOT spin. the housing can be rotated but it does not spin freely around.
What "collar" are you referring to

 

[Bt Doctur]

click to enlarge

 

[Mtl-Diesel]

click to enlarge

Sorry. Bad choice of words. I mean without the clamp that locks the unit down. I think it is #39 in the diagram.

 

[Scott Danforth]

the clamp is common across the inline 4-bangers as well as the 196/230/250/292 6-bangers. I believe its the same used on the V8's as well.

the parts diagram shows the two thrust washers, however doesn't show the two bushings in the body.

 

[Bondo]

the clamp is common across the inline 4-bangers as well as the 196/230/250/292 6-bangers. I believe its the same used on the V8's as well.

the parts diagram shows the two thrust washers, however doesn't show the two bushings in the body.

Ayuh,.... I agree, they're all the same,.....

There is an upside, 'n down-side,.....

It's got a slight curve, that puts more pressure on the distributor housin' to lock it in-place,.......

 

[Mtl-Diesel]

Ayuh,.... I agree, they're all the same,.....

There is an upside, 'n down-side,.....

It's got a slight curve, that puts more pressure on the distributor housin' to lock it in-place,.......

OK. It was installed correctly. What should it be torqued down to? I had to force to remove the bolt when I took it off. Prior to removing, I could not turn the unit by hand. However, with all the wires unplugged from the cap, when I turned the key the entire unit would rotate.