Engine won't run with proper timing

204Angler · **Posted:** Fri Aug 22, 2014 8:17 am

I mentioned this briefly in another thread. I fixed one issue (thanks to y'all) now I've got something else that actually existed before but, I wasn't too worried about it until now. It's the last gremlin before it will be 100% and I'm trying to get all this stuff done during break-in.

Right now the timing is set at about 16* advance. This is as far retarded as I can get it and it still idle smooth. When I bring it to 8* it dies. My tachometer is dead so I can't even hook the wire to the coil NEG. So I am not sure what my revs are exactly. However I do know, where it is idling now is definitely no more than 800. It shifts smoothly in and out of both forward and reverse. When I rebuilt the carb, I brought the idle adjustment screws to "zero" that is, bottom them out and back them out 3 full turns.
The other problem that is related (I think) is when it dies, the engine is extremely hard starting. It starts only because the battery(ies) are both healthy. All the connections are clean, tight with dielectric grease etc... What I THINK is happening is I am getting a spark so advanced that it is fighting the starter motor. i.e. I go to restart it, the engine will turn over a half a turn and suddenly the starter motor struggles to continue cranking, like I am having combustion in the cylinder too far advance.... HOWEVER, when I start the engine at the ramp when we are launching it, it starts great with no issues. Is my starter motor going south??
So, the idle-timing issue and the hard starting...
Thanks guys for all the continued help. Soon Ill have mine GTG and can help someone else!

rpengr · **Posted:** Fri Aug 22, 2014 9:56 am

I'm not sure what you have going on there. There is no reason it shouldn't idle just fine at 8 deg or even zero degrees timing.

You are correct that advanced timing causes harder starting, and retarded timing causes easier starting.

I'm thinking you have a distributor issue going on. Could the dist. cap have become rotated? (missed the notch when installing?) Do you need a new cap and rotor? If you have counterweights in the distributor, could you have a broken spring?

kd4pbs · **Joined:** Thu Sep 05, 2013 10:34 am **Posts:** 350

Indeed, as rpengr states... if the distributor is a tooth off from where it needs to be, it's possible that as you rotate the distributor to retard the timing, the rotor ends up being too far away from the correct lug for the proper cylinder to fire, and then it fires the wrong plug. That could be causing both issues you have.
Also, remember that as you retard the timing, you need to compensate with the idle speed adjustment.
As far as the idle mixture adjustment, merely turning them out the same amount of turns won't cut it. You'll need to properly set the mixture. Basically what you're shooting for is highest idle speed as you adjust each screw identically. Do a quarter turn on the port screw one way, and a quarter turn on the starboard screw the same direction. keep doing this until the idle drops. Turn them back the other way until the idle raises again and drops the same amount as it did before. Split the difference and you'll be pretty much where the mixture should be. If you have a vacuum gauge, then what you'll want is highest idle speed with the most amount of manifold vacuum, but the gauge is not a necessity.

If I could find a free moment, I'd be glad to head down there and help, but with school starting back Monday I think this weekend will be tough to find time to do anything. Hopefully last weekend wasn't the last time we get to use the boat this year...

kd4pbs · **Joined:** Thu Sep 05, 2013 10:34 am **Posts:** 350

Scratch that... the more I think about it, having the distributor a tooth off wouldn't make one bit of difference. The reason why is that the timing between the reluctor / pickup in the distributor and the lug that the spark plug wire is hooked to is always the same regardless of the distributor shaft. Perhaps it's all idle mixture and speed related.

Oh, and the hard start issue... that's more indicative of a too far advanced ignition. It starts fine at the ramp because the engine is cold. Once it warms up, then you get preignition at start, which indeed causes a little "clank" and strain on the starter every time it does it. It's the preignition actually trying to drive the engine backwards, and the starter will strain like crazy to do it. I don't know why it would do it more when it's retarded though - usually that goes the other way... more when it's too far advanced.

crossram · **Posted:** Fri Aug 22, 2014 11:09 am

like ever one else said the timing too advanced will give you a hard start when hot . a distributor off a tooth or so from top dead center will throw off the timing. put at dead center again on the number 1 cylinder and see where rotor is pointing. should be in the center of the cap terminal

LouC · **Posted:** Fri Aug 22, 2014 11:14 am

Ahh we need a bit more info.
Points n condenser, or electronic conversion?
To sort this out you need a good engine analyzer tach/dwell/volts/ohms meter and an advance timing light. Sears sells both and they are pretty cheap. I have the timing light from the old days when you could actually set it on our vehicles.
Then you can get your rpm and dwell accurately. I think you're on the right track the base timing is too far advanced for sure. In fact if you run it on the water with 16* advance you will burn up the engine more than likely.
If its a points dist you will have to remove the point plate and find out if the advance weights are sticking, it seems that they could be.
There is a wick in the center of the dist shaft, this is supposed to get a few drops of motor oil every year, that lubricates the weights so they don't stick. Could be a broken spring too. And the comment on the dist being one tooth off could be part of this problem.

if you still have the points dist, here are the OMC specs:

Dwell 39* +- 2* point gap=0.018"in
Timing, 1* BTDC regular gas, 6* BTDC premium
Idle speed 500-600 in fwd gear in the water. If you set it at 600 on land it will be close enough.

crossram · **Posted:** Fri Aug 22, 2014 11:19 am

when you say

204Angler wrote:

This is as far retarded as I can get it and it still idle smooth.

you mean the least you can keep it running at an advanced setting?

rpengr · **Posted:** Fri Aug 22, 2014 11:45 am

Ah, I was trying to remember if my '87 had points and condenser. I'm pretty sure it did.

Point gap out of adjustment can put the rotor out of alignment with the lug on the cap at the time of ignition. This sounds like your problem. If you don't have a tach/dwell/etc meter, you can still set the point gap with a feeler gage. Point gap and Dwell are two ways of adjusting the same thing.

(Find a mechanic with a significant amount of grey hair, and he should be able to fix this)

ric · **Posted:** Fri Aug 22, 2014 11:47 am

Also I'm not sure about what dist you have, but I know on the newer Volvo/Merc you have to ground the module before you set timing

204Angler · **Posted:** Fri Aug 22, 2014 8:47 pm

Wow guys, thank you for all the replies.

So yes, what I mean was it was the least amount of advance I could adjust it to and still have it idle smoothly. It will idle if I bring it down to lets say, 12* but it stumbles like it is trying it's best to keep idling. Below 10* pretty much stalls the engine.

That makes sense about the preignition when it is hot. About the carb, I followed the Q-Jet "zeroing" instructions. It says to back the idle circuit screws out 3 turns to START with. Until I got the rest of it figured out and wasn't going to mess with it. The reason for that is, I didn't want to fix a symptom or mask an issue and have other one's arise.

It is the petronix ignition system. So now points or condenser obviously.

I just came off the lake and tried re-stabbing the dizzy one tooth (I think) over. At first I thought it was fixed, because I checked the timing again but the dist. wasn't settled all the way in and when it did settle, the timing moved back to where it was before. I think moving it a tooth over will help, if not fix it. I was going to fix it again but we ran out of light.

This is frustrating. on top of this, the tilt/trim is stealing power again! .

Thanks guys again, for all the help and suggestions.

I will re-read y'alls posts when I get "unfrustrated" and go through things one at a time.

204Angler · **Posted:** Fri Aug 22, 2014 8:49 pm

kd4pbs wrote:

Scratch that... the more I think about it, having the distributor a tooth off wouldn't make one bit of difference. The reason why is that the timing between the reluctor / pickup in the distributor and the lug that the spark plug wire is hooked to is always the same regardless of the distributor shaft. Perhaps it's all idle mixture and speed related.

Oh, and the hard start issue... that's more indicative of a too far advanced ignition. It starts fine at the ramp because the engine is cold. Once it warms up, then you get preignition at start, which indeed causes a little "clank" and strain on the starter every time it does it. It's the preignition actually trying to drive the engine backwards, and the starter will strain like crazy to do it. I don't know why it would do it more when it's retarded though - usually that goes the other way... more when it's too far advanced.

That'd be awesome if you could help!! I sure could use it. I am about to bring it to someone man, seriously. I understand though, school starting up and all. No worries. Nice of you to think about it though

204Angler · **Posted:** Sat Aug 23, 2014 6:05 pm

OK, so I am here in the boat e setting the timing. However, the rotor still points to the same shoot I had it at last night when it briefly read 6-8*. As soon as I tightened the dizzy down it went right back to 16* I did retard it a tooth.
Would weak springs on the mechanical advance cause this? The weights are not sticky. It is a prestolight IBM 7021.
I will tweak idle adjustment screw's as well
I am young on my phone so forgive the spelling and lack of grammar

204Angler · **Posted:** Sat Aug 23, 2014 6:05 pm

OK, so I am here in the boat e setting the timing. However, the rotor still points to the same shoot I had it at last night when it briefly read 6-8*. As soon as I tightened the dizzy down it went right back to 16* I did retard it a tooth.
Would weak springs on the mechanical advance cause this? The weights are not sticky. It is a prestolight IBM 7021. Edit: rotor is pointed at about the 5:30 position
I will tweak idle adjustment screw's as well
I am typing on my phone so forgive the spelling and lack of grammar

204Angler · **Posted:** Sat Aug 23, 2014 7:11 pm

OK. So I am going to leave rotor at 530 position with cap on corresponding so rotor points at #1. I I'll mess with idle adjustment screws on carb. I have reset timing almost a oxen times with same result. This is almost becoming the definition of insanity.
I've been doing some reading and some dudes with new vortec and q jet freshly cleaned and rebuilt had their idle mix screw's out more than 4 turns +. Mine were set at three turns out. I any thing of anything else out could be. I will drop oil on advance mechanism. It moved freely. Curious if weak springs will do this? I'm guessing not since it was suggested the weights might be sticking.

I've got to go into work tomorrow for a bit, then church but after that I'll pull boat out of shop and hook hose up and play with the carb some

Interesting thing. The alternator is very warm, borderline hit to the touch. With our without power switch on!!! What could this be?
I will report back. If anyone had anything else let me know! Thanks gents

crossram · **Posted:** Sat Aug 23, 2014 8:57 pm

If 530 is on the number 1 wire terminal .Adjust the idle screw out till it just hits throttle linkage then 1/2 turn more to start. start with the idle a little high ,set the timing and adjust idle to specs. the advance weights and springs won't be the problem on idle they don't come into the equation till off idle

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Engine won't run with proper timing

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