Any other reasons it could crank but not start?

92 230B. It has good compression. New plugs, carburetor, wires, fuel pump, wires, dist cap, rotor, good fuel, good fuel pressure, and good timing. Or so I think.

The mechanic wants to tear it down looking for a head gasket leak but there is no water in the oil. I have never had a busted head gasket lead to it not starting.

Cranks great, BTW.

Could it be something dumb like an intake manifold gasket? I'm at a loss for sure.

JD

Mechanic's wife a has big credit card bill due....
If the engine has good compression, you don't have a head gasket leak...
Find another mechanic....

With all the stuff you had replaced and the "expertise" of the mechanic, I'd look at a mistake in the spark plug wiring (or gapping) first.
BTW... did it run before all the "fixes"?

Put the timing light on the #1 plug wire and see if you can see the timing marks? If not check all the plug wires until you see the timing marks. Follow that wire to the distributor cap and put the #1 plug wire on that tower on the cap and set the firing order from there and see if she pops.
clockwise 1-3-4-2 firing order

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jid said:

92 230B. It has good compression. New plugs, carburetor, wires, fuel pump, wires, dist cap, rotor, good fuel, good fuel pressure, and good timing. Or so I think.
Always...... always..... always use the P of E when making any changes and/or replacements. In other words.... test, repair, replace ONE ITEM only at a time. Move on to the next item ONLY after finding that the previous item checks out OK!


The mechanic wants to tear it down looking for a head gasket leak but there is no water in the oil. I have never had a busted head gasket lead to it not starting.
If he has not performed a cylinder "leak-down" test, and yet he recommends removing the cylinder head....... find another mechanic.



Cranks great, BTW.

Could it be something dumb like an intake manifold gasket? I'm at a loss for sure.
This OHC engine needs the following in order to start up and run:

a...... good compression (aka cylinder pressures)
b...... camshaft and counter-shaft phased correctly (it is not uncommon to see this OFF)
c...... good fuel delivery system
d..... good hot spark that occurs at precisely the correct time per cylinder



JD

Click to expand...

I'm really starting to wonder if the mechanic (or marina) are just not that smart.

The cylinders are all about 165 each so that is good. I didn't do a leak down yet but was going to pop the valve covers off today just to see if anything looked funny.

How do i validate that the camshaft and countershaft are phased correctly?

I am 100% certain that the plug wires are good (replaced them). I've got the firing order right. The mechanic verified that. I've bought more plugs to install today so i'm going to go that route.

The issue in terms of validating timing is that the motor has to fire in order to check the timing, correct?

Fuel delivery is definitely alright.

What are the chances that this is actually an issue with the the timing belt? the teeth look good.

If you have good cylinder pressures (and it would appear that you do), it may be safe to assume that the camshaft is indexed correctly with the crankshaft.

However, this does not eliminate the possibility of the countershaft being out of phase. The countershaft drives the ignition distributor.

I would check the indexing of both the counter shaft and the camshaft!

You will find the procedure in your OEM service manual.


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Update: I removed and reinstalled the timing belt to make sure that wasn't the issue.

Mechanic called me today and said he was coming to the boat so I met him there. We diagnosed a problem of intermittent spark. The coil always fires BUT the spark from the dist cap to the plug is super weak. I didn't have yet another cap, rotor, and condenser around. In fact, I'm sure if the mechanic replaced the condenser during the last tune up.

Suffice to say, those parts are ordered and I'll know on Sat if I can get a good spark or not out of this baby!

JD

Get a new coil as well and just put a ballast resistor to coil posative. It is very likely the reason it is cooking ignition parts. Be sure and gap the points with a dwell meter at around 62 degrees dwell between .014 and .015 inch gap.

The solution was: Replace the points with the pertronix ignition stuff. Took 15 min and the boat fired right up. 6 weeks and multiple service calls later going down the wrong path, the boat runs!!!

Thanks to all of you for your help!

Good on ya! I always replace points/condensor with electronics on all my old vehicles. Just makes sense especially in a moisture rich environment like a boat.