Timing Question

[BAproject]

Hi All,

As I am still new at this whole boat repair and restoration I have made a few mistakes along the way.

When I pulled the intake manifold off to inspect, clean, etc...I did not mark the position of the distributor. Luckily the clamp that holds it down had left indents in the paint so I was able to line it back up properly upon installation.

Of course thats not my problem. With the distributor out I accidently turned the engine. Now I read in the manual you are not supposed to do this, but I read it after it happened. The good news was then engine turned fairly easily (no plugs in it right now) after sitting for 5 years, so I doused the cylinders with mystery oil and turned it around a few times to make sure it was nice and free.

Sorry for the long post! So the distributor is keyed and it seems that it can only go in in one position which I have successfully done, but I am wondering if I really screwed up the syncing on the distributor gear and will I be able to diagnose better with a timing light? Please help! I am afraid to even try and start the engine if the timing is screwed up. and as far as I know to properly time an engine it must be running.

-BAproject

 

[bruceb58]

Re: Timing Question

Rotate the engine to TDC where the #1 piston is coming up on the compression stroke. You can stick a finger in the spark plug hole to determine this. Then drop the distributor in so that the rotor is pointed to the #1 spark plug wire. You can time your engine with a timing light at that point.

 

[BAproject]

Re: Timing Question

Awesome! Thanks Bruce! Sounds pretty easy....knock on wood. I figured that the way it's keyed it can really only go in one way. I will set everything using your advice....and then adjust it from there.

Thanks again.

-BAproject

 

[bruceb58]

Re: Timing Question

Not sure what engine you have but the "Keying" you mention is more than likely the oil pump engaging into the distributor. Just drop the distributor in until it is engaging with the cam gear and then rotate the engine again after that. The distributor will fall the rest of the way in once it lines up with the oil pump rod. Then check the distributor alignment again. You need to compensate for the angle of the distributor gear when you drop it in since it will rotate a bit as the gears mesh.

 

[BAproject]

Re: Timing Question

Hi Bruce,

It's a 4.3L V6 Mercruiser ('91), I'm not sure what the part is that the distributor is engaging with is, but makes sense that it would be the oil pump. So I will line up the drive with TDC and then drop in the distributor and adjust accordingly. Just one quick question, the balancer lines up with the tab on the timing chain cover, that should indicate when TDC is achieved, correct? You mentioned sticking my finger in the plug hole to feel, is that necessary or can it all be done from the tab on the timing cover?

Also, since you mentioned it , I have read some post here about spinning the oil pump for a bit for engines that have sitting for extended periods of time. Is this the thing you spin with a drill extension? This motor has not been run in 5 years :O.

-BAproject

 

[howlnmad]

Re: Timing Question

Hi Bruce,


Also, since you mentioned it , I have read some post here about spinning the oil pump for a bit for engines that have sitting for extended periods of time. Is this the thing you spin with a drill extension? This motor has not been run in 5 years :O.

-BAproject

It sure won't hurt a thing to prime the oil that way. I made one from the blade of an old long shank regular screwdriver with the handle removed and chucked into a hand drill. I slid a socket over the shank that would fit over the oil pump shaft (to keep the blade from sliding out of the pump shaft) but can't remember what size it is off the top of my head.

 

[BAproject]

Re: Timing Question

Excellent, now here's another thing, what are the odds the oil pump can seize up. I have not tried to turn it but now I am having one of those freak out moments where I think it may be stuck....hope I'm just being paranoid....if the engine turns I assume the pump turns with it?

 

[bruceb58]

Re: Timing Question

It would definitely be a good idea to run the oil pump. I would buy the tool rather than making one up.

http://www.tooltopia.com/index.asp?...&utm_term=KDT3446&utm_campaign=googlebase_18u



You have to line up the timing mark but you still need to feel for the compression stroke. When you have the timing mark aligned you can either be at the top of the compression stroke or top of the exhaust stroke. Remember...you have a 4 cycle engine here.

 

[bruceb58]

Re: Timing Question

Excellent, now here's another thing, what are the odds the oil pump can seize up. I have not tried to turn it but now I am having one of those freak out moments where I think it may be stuck....hope I'm just being paranoid....if the engine turns I assume the pump turns with it?

Yes...the pump turns but only if the distributor is installed.

 

[BAproject]

Re: Timing Question

Hi Bruce,

Correction, I have a V6, so it could still be either or, I will feel for the piston then.

Unless, a 6 cylinder changes things...

It makes sense to get that tool, but how can I do all that with the distributor installed per your last post?

 

[bruceb58]

Re: Timing Question

Before you drop the distributor in, prime the oil pump and get everything up to pressure. You can turn your ignition on and actually see the oil pressure rise on the gauge. Put in new clean oil before you do this obviously.

 

[BAproject]

Re: Timing Question

Ha....

...You're assuming that the pressure gauge is working properly

Just another piece to the puzzle I guess. I would be surprised if any of the gauges work properly after sitting for 5 years, mostly outside and uncovered

-BAproject

 

[howlnmad]

Re: Timing Question

Just out of curiosity, how long has this boat sat without being turned over?

 

[Silvertip]

Re: Timing Question

You need to understand that even though the timing mark on the balancer lines up with the "0" on the tab, you can still be out of timing by 180 degrees. An engine rotates twice to make the distributor turn once. So with one crankshaft revolution the distributor only turns 1/2 turn or 180 degrees. You MUST make sure the #1 piston is on the compression stroke - not the exhaust stroke.

 

[bigskiohio]

Re: Timing Question

rotor should point at the direction of no .1 wire on the cap,that gets it close then you will rotate the distr. to get it right when it is running. thumb over hole for comp. stroke.

 

[BAproject]

Re: Timing Question

Howlnmad,

It's been five years since she was running. Had to rebuild carb, alternator, replace the t-stat housing and waterpump, clear out the heads and intake manifold...etc...etc...and in the process of trying to get the ridiculously placed starter out.

It turns so now I just have to get it started, verify compression in every cylinder and tune everything.

-BAproject