Yet Another Starting Problem Saga

[campbdon]

Hello fellow Afourians. I truly enjoy reading though the many threads on this site and feel my knowledge has improved immensely from your suggestions. To get to the point, I likely brought this problem upon myself but after a long layup I am in possesion of an A4 unable to start. Apologies for the long-winded description to follow...

Background:
Due to COVID 19 did not launch in Spring 2020. Thus boat (Northern 29 1977) was in disuse between Oct 2019 (haulout) and June 2021 (launch) being 1.5yrs. During layover I replaced the Keyed+Pushbutton starting mechanisms with a 3-pos keyswitch. Why?, because some years ago the key broke off in the switch and I hotwired/bypassed it, requiring batt selector (1,2,both,off)be switched to one of the 2 batts then pushing the start button. I didn't like this kludge so decided to normalize it. After the install I verified that the starter would try to turn over the engine but I never went further to verify that the engine would actually start. Therefore the engine was never run over the layover period. My bad.
Winterizing was as per usual for past 10 seasons (plumbers antifreeze plus pull drain plugs), oil in plug holes, etc)
Before launch this spring I tried unsuccessfully many times to start up. Always while attempting starting water intake shut off as widely advised.

Symptoms:
When key is switched to Start there is the usual sound coming from the starting motor and I'd descibe the starting as 95% complete. It just won't turn over. With 1-2oz fresh gas poured into arrestor, full choke (verified at carb throat)and 1/4 throttle with switch held on Start there is a fast "hrump-hrump" sound of exhaust pressure, like motor is on verge of running, and with some smoke. I hold this for up to 5-10sec then when key is released back to ON all starting attempt stops. Key turned back to OFF ASAP. As mentioned besides being idle for 1.5 yrs the only change made was the key switch so I retraced all the wiring to/from it and compared with wiring diagrams published on this website. Nothing obviously wrong stands out. So I focused on the main ingredients of successful starting, namely fuel, spark, and compression not only to solve the starting problem but improve the overall environment

Other notes:
- Oil looked clean. No discolouration or smell of gas or evidence of water

Actions Taken:

a) SPARK
-Centre wire from dist placed near block. Switch on using remote starter. Spark at least 1" seen. Cannot distinguish if yellow or blue. With each plug removed and on its wire also see sparks to ground on all 4. Plugs looked good but replaced with new anyway.
-EI is installed (no points). Inspected dist cap, looked a bit dirty on all contacts and rotor contact, so cleaned. Replaced with new dist cap (
NAPA RR181 Distributor Cap). Made no diff
-EI module led flashes as usual and rotor(?) inside dist rotates when starting
-Spark plug wires all <1Kohms resistance (ok?)
-Solenoid "S" post to ground approx 2ohms
-coil voltage drops slightly from 13v 11.5v when starting
-Short batt post on solenoid to "S" term with screwdriver gives possibly stronger start attempt but no start. Remote starter connects same way.

b) COMPRESSION
-pressure gauge on start attempt approx 60psi all cyl. Cannot hold thumb on plug holes while cranking.
-poured a few oz MM Oil into each cyl on several occasions
-whacked solenoid and starter with piece of wood while starting

c) FUEL
- New fuel pump installed (477060 FACET GOLD-FLO FUEL PUMP)
-Carb removed, cleaned and rebuilt using MM kit (gaskets, main needle)
- OPSS bypassed to ensure fuel pump received 12v
- Used gerry can with fresh fuel to pump via short hose
-Inline filter inspected/cleaned (gas tank-pump-filter-carb)
-No gas seen in carb throat. Good suction at throat while cranking.
- When carb bolts loosened evidence of some gas seen on gasket to intake manifold
- Could not determine if smell of gas on the plugs
- Fuel tank drained of old gas and soaked in Methyl hydrate hoping to clean any remaining junk. Not using tank for troubleshooting.

Next Steps
- Am about to consider removal of solenoid/starter for inspection, possibly replace solenoid
- Already booked appt with mechanic from the marina for assistance.

Thanks for your time and appreciate any input!
Thanks
Donc

[JOHN COOKSON]

Originally Posted by campbdon

Symptoms:
When key is switched to Start there is the usual sound coming from the starting motor and I'd descibe the starting as 95% complete. It just won't turn over. With 1-2oz fresh gas poured into arrestor, full choke (verified at carb throat)and 1/4 throttle with switch held on Start there is a fast "hrump-hrump" sound of exhaust pressure, like motor is on verge of running, and with some smoke. I hold this for up to 5-10sec then when key is released back to ON all starting attempt stops. Key turned back to OFF ASAP. As mentioned besides being idle for 1.5 yrs the only change made was the key switch so I retraced all the wiring to/from it and compared with wiring diagrams published on this website. Nothing obviously wrong stands out. So I focused on the main ingredients of successful starting, namely fuel, spark, and compression not only to solve the starting problem but improve the overall environment

Donc

Also the choke needs to be closed all the way and spark must occur at the right time.

Are the spark plug wires in the correct firing order, 1,2,4,3? Has the distributor been rotated so the spark is not occurring at the right time?
Is there tracking or shorting inside the distributor cap between terminals?
Popping out the exhaust makes me think the spark plug(s) are firing when the exhaust valve(s) is open.
Try to start the engine with starting fluid. This will tell you if the problem is fuel or ignition related.
A fuel pressure gauge would be helpful.

Others will be along soon with more ideas. Hang in there.

ex TRUE GRIT

[edwardc]

Sounds like you're doing a thorough, methodical approach.

Don't bother removing the starter/solenoid. From your description, it sounds like the engine is turning over but not firing. I base this on the statement that you are getting spark to each of the 4 plug wires. Similarly, this eliminates the EI module as the problem.

60 PSI is pretty low compression, but it should be enough to start. When testing compression, you should remove all 4 plugs, and have the throttle wide open and the choke off. Failure to do either of these will produce lower readings.

I would focus on fuel delivery and timing.

To test for a fuel problem, shoot a 1-sec blast of starter fluid into the flame arrestor, and then try to start. If it fires and tries to run for a couple of seconds, then dies, you have a fuel delivery problem. If not, then you have a timing issue or sticky valves. Check that all the plug wires are in the correct order and placement.

Good luck, and keep us posted!

[joe_db]

60 PSI is what - 4:1? That would be a barely working engine at best.

[campbdon]

Actually I don't recall whether 60 or 70 PSI (pounds per square inch). Not sure what you mean by 4.1 but in any case I'll need to repeat the test following the advice of using full throttle. I made the measurement with all plugs removed and moving the gauge from one cyl to the next. The engine was obviously not warmed up first and at least the measurement was consistent across all 4 .

[Sam]

Just had a similar problem and situation. My 66 Morgan 34 w/original early engine was winter layed up Oct 2019 and continued covid layed up till June 2021. My SOP layup is to drain all fuel lines/filters. This year prior to launch I did not like the idea of 2yr old gas in the tank [above engine under cockpit] and pumped it ALL out rather than just bottom couple of gallons. I added 9 gallons of fresh gas [ less than 1/2 tank] and tried to start. First time in recent memory the engine did not start even with a little foreplay. Starting fluid indicated a fuel delivery problem- even though bulk head mounted facet pump is only 3yrs old. After sleeping on the problem it occurred that the pump does not initially create enough "lift" and resultant siphon pressure with empty fuel lines and a partial filled tank which is above the pump and carb. I added just 3 more gallons of gas with the can that I had and used a turkey baster to fill the fuel lines - call it priming. Engine started right up and the next day we went on 5hr river bridge run [27 city bridges] to the harbor where we filled the tank.

Difference this year was emptying the tank completely and not immediately refilling near full before starting. Point is that the Facet is good at creating and maintaining 1-3psi of downstream pressure but may not give you the initial lift and syphon on a less than half empty tank & fuel lines especially when the pick up tube is another 1 1/2 inches off the bottom. If this scenario fits fill the tank and lines and give it a try.

[chapster5]

Hmmm, this is one of those times when having a fuel pressure gage between the fuel pump and carb would be handy.

You do not have one of these correct ??

Chapster5

[roadnsky]

Originally Posted by campbdon

Actually I don't recall whether 60 or 70 PSI (pounds per square inch). Not sure what you mean by 4.1 but in any case I'll need to repeat the test following the advice of using full throttle. I made the measurement with all plugs removed and moving the gauge from one cyl to the next. The engine was obviously not warmed up first and at least the measurement was consistent across all 4 .

COMPRESSION TEST PROCEDURE
Test the engine while its warm, as you'll get different readings hot and cold.
Your readings will be higher on a hot engine, but if it passes cold it will pass hot.

1. Make sure water intake is shut off so you don't fill exhaust system with water which will then enter the cylinders.
(You're not actually going to run the engine during the test so it won't need any cooling)
2. Remove spark plugs. Cover holes with a rag.
3. Remove coil wire, disable fuel pump if electric
(remove fuse or disconnect wire)
4. Open throttle to wide open and leave it there.
5. Be sure choke is OPEN completely
6. Screw tester into spark plug hole #1 and crank engine with starter for a few seconds.
You'll see the pressure on the gauge go up in steps and thenmax out.
When it tops out, that's the reading.
7. Repeat on the other cylinders.

If the readings are low or vary more than about 10% from one cylinder to the next, add a tablespoon of motor oil through the spark plug hole of the low cylinder(s).
If this increases the pressure significantly, it indicates worn rings or valve guides (the oil acts to seal the gap somewhat).
If it doesn't change it's more likely a valve that's sticking or not closing all the way.

[campbdon]

Thanks roadnsky (and all others). I will be following up on these suggestions over the next few days. A fuel pressure gauge (with brass barb-NPT fittings) is on its way. Maybe more significantly is that I discovered what appears to be some wiring errors following my recent ignition switch replacement. Specifically , there is a wire connecting the COIL + to SOL "S" and another wire between IGN and SOL + (big term). They don't appear in any wiring schematics I've seen. Also I need to verify that IGN post on the ign switch is indeed connected to COIL + (the usual purple wire that is hard to trace thru the wiring harness)
I will report back on what's up ASAP.
Thanks again!
DonC

[campbdon]

Sorry roadnsky, which wire at the coil is this (I have a few)?

"3. Remove coil wire, "

[Dave Neptune]

The wire from the coil to the cap. Remember to turn the key OFF in between cranking so you don't "fry" the coil.

Dave Neptune

[campbdon]

So, the wire from coil to centre of distributor?
Also, I expected to use my remote starter for this test (shorts SOL + to "S") so first switch ign to ON (not start) then squeeze starter (then go back and switch ign to off so as not to risk frying coil)?

[JOHN COOKSON]

Originally Posted by campbdon

(the usual purple wire that is hard to trace thru the wiring harness)
DonC

Wiring harness can be bad news if they have plugs in them. Moisture can get get to the plug contacts through the two halves and cause major, big time corrosion.
I got so tired of chasing wiring problems on my boat so I rewired the whole shebang using one wire A->B. No plugs in between A & B. Whenever I had a problem I knew it was not wiring problem.

It is not necessary to "trace" wiring through a harness or any other circuit. Disconnect the wire at both ends, attach a jumper wire to one end, and take a ohm reading at the other ends of the wire and the jumper wire. S\B zero ohms, of course. You can check for grounding back to the battery this way also.

ex TRUE GRIT

[campbdon]

Starting problem solved (it seems). Wiring mistakes while converting the old Key + push starter switch to 3-pos keyswitch as follows:

a) Keyswitch ON post was connected to SOL +. Removed from SOL + and connected to COIL +
b) Keyswitch ST post was connected to BOTH SOL "S" and COIL +. Removed wire connecting SOL "S" to COIL +
Engine now starts but further work to come checking timing , adjusting idle setting (stalls if drops below ~1000RPM), plus other improvements.

The yellow cover "Atomic 4 Marine Engine" service and repair manual p48-49 revealed what was wrong.

Thank you so much for the helpful suggestions.
DonC