Advice please

[Peter]

Hello all,

Blew up my Atomic 4 - hole in wall of #3 cylinder. Have a line on a replacement. Here is what the guy just sent me.

"and we fired up the engine. Great steady oil pressure starting at 25lbs. and after 1 hr. of on again off again rough running it increased to 30 to 35 lbs. It started almost immediately but ran a little rough. We replaced two bad spark plug cables and it ran a little better but according to my son still not running right as it would not rev up but sputter out. We tried several carb. adjustments but no success. To eliminate a compression/ sticky valve problem we did a compression test. All cylinders showed between 92 to 94 lbs. solid on the gage. Next we checked for a leaky intake manifold using an unlit propane torch but no increase in RPM was shown so the intake manifold gasket was tight, no problems there. My wiz. Kid mechanic son then declares it’s a carb. and a tune up in general problem . The fact that we found the gas in the fuel water bowl had turned to varnish and the engine tended to run a little rougher with time seems to back this up as the old gas varnish particles in the carb. would have been diluted and breaking away in particles blocking the jet. I have 100% confidence that the engine is top notch because of the oil pressure and compression readings. "


He previously told me the engine was used for one season, was properly mothballed, still has original factory paint and no rust on it.

I plan to go look at the engine.

Any comments advice appreciated. Is this a go for it or a run away screaming engine?

Thanks,

Peter

[BunnyPlanet169]

Welcome to the Forum!

IMHO, running condition, with known oil pressure and compression, is a Good Thing. The carb and fuel pump almost certainly need a thorough multi-solvent cleaning, if not rebuild - MMI has the kits - and it's pretty simple. Cooling system is unknown, but if it was really only used one season (??) then it's unlikely to be full of rust crispies. You'll probably plan on replacing water pump impeller, plugs, etc. Normal stuff.

Comes down to price. What are they asking?

[JOHN COOKSON]

Another welcome to the forum.
As BP said it all sounds like pretty simple stuff.
It depends on your temperament and time and pocketbook.
If possible it would be a good thing to confirm the compression readings yourself.

TRUE GRIT

[sastanley]

Hi Peter,
Does 'properly mothballed' also mean they drained all the ethanol fuel out of it after mothballing? I doubt it, and I bet that is most of the issue.

The rough running may allow you to negotiate the price down a little bit, but it sounds like it's OK to me. In addition to the possible fuel problem, it could have old points in it, the advance weights could be stuck..any number of things.

It certainly sounds like it is in better condition than the one you have now.

[Peter]

Dear Afourians,

Thanks for the sage and prompt advice. Went to see the motor today.

Started just fine. Could not open throttle unless the choke was closed, even after it warmed up. o/p, on a direct mechanical gauge, was about 30 lbs. Did a compression check, and each cylinder was within a few pounds either side of 100 - lowest was 98 and highest 105.

no water or oil leaks. Hoses in good shape.

Mothballed - it had been filled with anti-freeze and the water coming out of it when running looked pretty clean - no big chunks anyway. All the cylinders had been filled with oil the chap told me. Not sure if the crankcase had been done with fogging oil.

Put it in gear and it went around, put it in gear the other way and it went around the other way. It was a little tricky to find neutral - issue?

No mods to engine - mechanical fuel pump, no bypass restrictor on cooling system.

Looked at points and rotor and they need replacing - he had a box of spares from Moyer than included points, rotor, condenser.

Oil was clean as a whistle.

Fuel had NOT been emptied from carburetor for storage so it would require a good cleaning. On the other hand, until my engine went belly up, it ran just fine so maybe a carb swap would do it.

He wants $1000 for it.

Of course, I have also been looking at a diesel re-power. There is an old 1962 boat that somebody re-powered 4 years ago with a Beta 14 that has 70 hours on it. He is asking $3600 but I am pretty sure I could get it for maybe $3k. So I went to look at it today. Boat is in very rough shape so no qualms with a remove engine - part out - scrap scenario. While looking at it I got talking to another fellow in the yard who, lo and behold, had re powered his boat this past winter with a Yanmar - to replace his A4. He told me the A4 ran just fine but was a little hard to start when hot. To make a long story short, at the cost of one bottle of rum, I have his old A4 in the back of my car now. Will run a compression check on it to see if it is salvageable.

It has an electric fuel pump, dip-stick extender, by-pass restrictor - so it looks like at least part of it's life was spent in caring hands.

I suspect I will be back with more questions...

Thanks again,

Peter

PS - as an old petrol head, I am biased towards the A4 as I understand gas engines.

[JOHN COOKSON]

Put it in gear and it went around, put it in gear the other way and it went around the other way. It was a little tricky to find neutral - issue?
PS - as an old petrol head, I am biased towards the A4 as I understand gas engines.

Finding on an A4 neutral can be a bit elusive - even in a properly adjusted transmission. The most important thing is to have a neutral. You will get used to where neutral is after some time with her - I mean it -orrrrrr maybe I do mean her.
Some say a gas engine is not a good engine on a boat. The gas engine was and still is a plus for me because like you I am familiar with carburetors, points, coils, dwell, timing 4 strokes and so on. Diesels on the other hand I know nothing about. If I had a diesel on my boat there would be a learning curve involved.

TRUE GRIT

[BunnyPlanet169]

Peter:

For a bottle of rum and $1000, I would have taken them both!

As attractive as a diesel re-power may seem, in practice it's a very expensive option compared to replacing an A4. I went down this road mentally a couple years ago in a moment of weakness.... Not only do you have the cost of the engine (and my Beta quote was like $10K), by the time you're really finished it's probably also the fuel tank, all the instrumentation, a bunch of wiring, motor mounts, and probably the exhaust system.

All that might make sense if you have a valuable boat. I have a boat that will never be worth more than several thousand dollars. It has no significantly greater value with a diesel, and it's essentially worthless without an engine.

[Peter]

Hi all,

Thanks again for all the helpful replies. Getting ready to try to fire up the "bottle of rum" motor. Following the attached wiring diagram.


Question - the engine has electronic ignition, with a red wire and a black wire going into the distributor. It is currently wired with the red wire to + on the coil and the black to - on the coil. Correct for the EI?

Peter

[BunnyPlanet169]

That's correct.

In the picture, you can see the red and black wires for EI, and the black for tach, all attached directly to the coil studs.

There's a number of things powered off the wire from the ignition at coil +, enough so that I put a terminal block there. I think others have done the same.

+ volts from the ignition switch
Excite wire to alternator
Power to OPSS and fuel pump
EI + volts

[ndutton]

Question - the engine has electronic ignition, with a red wire and a black wire going into the distributor. It is currently wired with the red wire to + on the coil and the black to - on the coil. Correct for the EI?

Correct.

Important because you have EI
With a volt/ohm meter on the ohms scale measure the resistance between the two small posts on the coil (wires removed from one of the posts). The resistance should be in the area of 3~4Ω. Reconnect the wires and after you start the engine measure the coil input voltage (tester probes on the small coil + post and the engine block) with the engine revved up slightly so the alternator is producing. Divide the measured resistance into the measured voltage. If the quotient is less than 4 you're golden. If not there is a simple remedy.

This test takes seconds to perform and can save you hours of grief.

[Peter]

Hi all,

Thank you again for your assistance.

I just fired it up and it started right away and ran very nicely. Great throttle response. Went into forward and reverse quite nicely as well.

I re-circulated the cooling water in a bucket and it was not totally disgusting - a light grey/brown color and no particulate matter which i find encouraging. I did not run it for too long this way and the water is warm but not so hot i cannot put my hand into it.

Question #1 - I do not have an oil pressure gauge here but I put an ohmmeter on the sending unit. While running it read between 101-102 ohms depending upon rpm. When I shut it off it went to 98.9 ohms. Any idea if this means op is ok? (I do have a new sending unit and gauge on the boat on the old engine but that is 5 hours drive away...)

Question #2 - Big leak around water pump - which is a Sherwood. I have an Oberdorfer on the old engine. I think I will switch to that. Is the flange gasket the same? I suppose it must be but you never know.

Question #3 - it has a FACET fuel pump and it seems to run all the time - making a clicking sound. Is this normal?

I did the coil/voltage measurements - coil resistance - 4 ohms. Voltage with a few rpm on - 14.5 Volts. Ratio = 3.625 so that is ok.

Peter

[BunnyPlanet169]

1) Depends on gauge /sender manufacturer. Usually 240 ohms (no pressure) down to 35 ish. Both ISSPRO and SW searches on the internet show this range.

2) I would agree, and only one gasket on the MMI page...

3) Depends if you have an OPSS - the fuel pump will run all the time if the power comes from coil + (switched ignition) and no OPSS. The fuel pump will only run with minimal oil pressure if you have an OPSS (about 6psi - will turn 'on' at cranking pressure usually).

PS - for a bottle of rum, that was a very good deal!

[Peter]

Again thanks for input

1) My neighbor has a screw in type oil pressure gauge - might see if I can borrow it this evening. Do not want to install this puppy if the OP is not good.

2) OPSS - the engine does have one - I should put it in the positive line for the fuel pump?

Yes, I am thinking I got a pretty sweet deal!

Peter

[BunnyPlanet169]

2) OPSS - the engine does have one - I should put it in the positive line for the fuel pump? Peter

Correct. Typically the circuit is Coil + -> Fuse holder @5A -> OPSS -> fuel pump. The pump mechanically makes the ground.

Yes, I am thinking I got a pretty sweet deal!

You did.

[BunnyPlanet169]

Question #3 - it has a FACET fuel pump and it seems to run all the time - making a clicking sound. Is this normal?
Peter

Thought I should add this safety note if you were not aware.

The OPSS is mandatory if the fuel pump is electric. The regulations require the electric pump to ONLY operate while the engine is operating. By powering the pump thru the OPSS, this condition is met, even if you leave the ignition 'on'.

You can find the Standards page here... http://www.moyermarine.com/forums/forumdisplay.php?f=86