#1
IP: 65.94.63.211
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Everything is hot
Got the old thing running today. Runs fine at idle load/no load, no choke, spitting out water fine 20 minutes..
Try going up on the throtle runs for a minute then shuts down. Just before the shut down it sounds like there is nothing in the exhaust, sort of an empty sound, then the shut down, then about 10 seconds later I can hear water sizzling somewhere in the system. I read about 450F off the exaust pipe. The flywheel cover is hot to the touch. The coil is very warm, While running the thermostat cover is about 80-90F. Today was hot 30C+ Should I yank the themostat and see what happens? If the thermostat was not doing its thing, and there was a blockage in the cooling would the engine be shutting down from overheating? I did blow some air through the exhaust to check for flow, and that seems to be ok. Next to no back pressure I don't have a water temp sensor hooked up, so I don't know what the water temp in the head really is, I am just using a IR temp meter. |
#2
IP: 24.152.132.140
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Although your post didn't specify, assuming you are raw water cooled here is a table of running temperatures taken with an IR temp gun all over a good running RWC engine with the new MMI thermostat. Offered here for comparison to what you are reading.
Your report of water flow stopping is not good. About removing the thermostat, unless you also block the bypass you risk making things worse.
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Neil 1977 Catalina 30 San Pedro, California prior boats 1987 Westsail 32, 1970 Catalina 22 Had my hands in a few others Last edited by ndutton; 08-23-2020 at 09:20 PM. |
The Following User Says Thank You to ndutton For This Useful Post: | ||
Ando (08-25-2020) |
#3
IP: 32.211.28.40
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First run? Cooling water is probably picking up and moving a lot of crud.
Definitely remove the thermostat until you get it running cool. T'stat will stop a lot of crud right there. Another classic spot is the output elbow from the manifold. I got mine running cool even after installing the heat exchanger. Decided I liked it that way and left it running cool. |
#4
IP: 65.94.63.211
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no love
Pulled the Tstat today, still runs at idle and spews water no problem. Turn up the RPMs and she shuts down almost instantly. I can hear this weird sound coming from the exhaust just before the crib death. Ten seconds after shutdown I can hear water hitting something hot.
Going to try to hook up the temp gauge next time to get an idea about temperatre. When I got the boat (8 years ago) it had a temp meter that allways sat at 130F, that was because as I found out later, it was not actually connected....So I may never know if there was a developing temp issue.. Anything I can look for at this point? |
#5
IP: 71.38.112.42
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Quote:
Quote:
450-500° is just about normal. Quote:
Any noise coming from there? Quote:
That thermostat cover temp is actually pretty low. Certainly not Hot.
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-Jerry 'Lone Ranger' 1978 RANGER 30 |
#6
IP: 100.36.65.17
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Check and replace your water pump impeller. It might be ceasing to pump at higher RPMs
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@(^.^)@ Ed 1977 Pearson P-323 "Dolce Vita" with rebuilt Atomic-4 Last edited by edwardc; 08-25-2020 at 01:43 PM. |
#7
IP: 65.94.63.211
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RPMs
I can run the engine fine at idle (very low RPM), as soon as I move the throtle more than 1 or 2mm on the arm on the carb she speeds up just a little and then stalls right out.
I can't get anywhere near the RPM I would expect to normally have. The sizzling I think might be water coming back down the exaust and making contact with the hot pipe, as to why it takes about 10-15 seconds after the shutdown, I have no Idea. Water pump is fine, I opened it up, all is good. Will try to get more temp readings tomorow |
#8
IP: 73.172.91.135
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Maybe you just have a problem with the main jet in your carb (separate from the idle jet, which seems to be working fine). Could it be that your engine is just normal hot but not overheating?
Check out this carb video from Moyer: https://youtu.be/kHuemGC_PHA?t=168 |
#9
IP: 65.94.63.211
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Water ethanol and more fussing about
I pulled the carb off yesterday, (I have a spare) when I drained it the fuel that came out looked a tad bit milky....Fuel coming out of the fuel system is crystal clean. I am going to take a guess and say that water is somehow getting in carb. I have a cover that sit's over the flame arrestor as the FA sits under the stair piece and is in no way protected from rain water.
I am going to check for the presence of ethanol later today, even though I use 100% gas everytime--Or so I have been lead to believe... |
#10
IP: 65.94.63.211
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More to note
Today it was a bit cooler and dryer than what we have been having last few weeks.
The beast starts OK with full choke, warms up, I lose the choke, runs for a few minutes and dies. I have put in valve after the water T inlet. I also re installed the alternator, thinking perhaps the ignition coil was not getting enough juice. Anyway, it seems like every time I start, it runs for for less and less time with each attempt. It's got brand new SAE 30 oil three days ago and is right in between Full and Low. If it is running and I try to up the RPMs she dies right away. If I let idle with or without choke she dies sooner or later (within 10 minutes) This leads one to think it is temperature related, but changing the valve settings seems to not have any effect, and water is being shot out the transom regardless of the valve setting (full close, full open, 25/50, 50/50 etc) The coil is cool today, both batteries are healthy. OP reads 50PSI and allways has unless run for long times then it would dip to 40/45 PSI And this mysterious post shut down sound is still happening What am I missing here??? Someone set me straight here on one thought; If the oil pump were to be NFG, I would assume the oil pressure would drop to 0, yes? Should I swap out the coil yet once again? Should I stop spending time on this early model and focus on the rebuild? |
#11
IP: 73.172.91.135
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Did you confirm that you have raw water cooling, ie, no heat exchanger? Is the water coming out the back warm or cool? It should be warm.
If you have a heat exchanger, have you checked the level of coolant? |
#12
IP: 71.38.112.42
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Quote:
How was this resolved?
__________________
-Jerry 'Lone Ranger' 1978 RANGER 30 |
#13
IP: 65.94.63.211
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Follow up #1
It is raw water cooled (no heat exchanger)
I did not check the water temperature exiting, kind of tricky on my boat but I guess I can lower a bucket to catch some water. The carb thing is strange, I did not figure out how water may be getting in, the other carb gave me trouble as I forgot that the throttle arm is broken and did not have any means of securing it, so I restored back to the original carb. I do have a 3rd carb that I will swap out today just for FUN.. I will swap out the coil as well just to see if that makes any change. AND I will see if I can get water a temp sender to talk to the gauge. |
#14
IP: 98.117.4.37
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Fuel supply
Splashlog,
Your most consistent current symptom, which has remained throughout your thread is that the engine starts and runs fairly well at idle but shuts down at higher power settings. I'm guessing that it will start up almost immediately with the same symptom prevailing? This particular symptom is very consistent with a fuel pump failure which lets you trying to operate on gravity flow alone. Is your fuel tank level with or slightly above the engine? Don |
The Following 2 Users Say Thank You to Don Moyer For This Useful Post: | ||
JOHN COOKSON (08-29-2020), Sam (08-29-2020) |
#15
IP: 73.208.164.69
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Once again the often recommended 0-15psi fuel pressure gauge installed between the pump and carb would be very informative. Inexpensive and easy to install [with adapter]. If Don's suggestion is right you would see the pressure drop to near zero from 2-3psi. [Suggest Marshall liquid filled stainless steel w/glass lens]
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The Following User Says Thank You to Sam For This Useful Post: | ||
sastanley (09-02-2020) |
#16
IP: 47.142.134.119
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Quote:
IMO there is a high probability this thread would have never happened if there was a fuel pressure gauge installed. When you do the fuel pump work it will be good opportunity to add a fuel pressure gauge. ex TRUE GRIT |
The Following User Says Thank You to JOHN COOKSON For This Useful Post: | ||
sastanley (09-02-2020) |
#18
IP: 65.94.63.211
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10000+
Three times I have unplugged the hose from the pump and it pumped gas into a cup at great velocity so I wrote it off as good. I did get a pressure gauge but when it arrived it stated clearly that it was not for use with gasoline...I now have something else on order.
For Don; the bottom of the tank is pretty much inline with the top of the engine. The top of the pump is basically flush with the top of the tank. It's the pump that came with the boat (Carter) and so I have never had any reason to suspect it as everything was working great since 2012 until late last season when unexpected shutdowns began. That event sent me down the rabbit hole at which point I figured it was likely a dirty carb as I had never done any service on it at all and seemed the most likely cause, I then moved to look at the coil while at the same time installing EI and thus creating more problems with incorrect timing, and a wiring error. A few days ago when I ran everything at low idle just so I could move some oil around to do the long overdue oil change, everything was getting hot, including the fuel pump which I thought was odd. So I will now take a closer look at the pump. It makes sense that it might be ok on a cold start and function well for a time, but perhaps could be overheating/failing after some run time. Which would explain why the run time seems to be shorter and shorter with every subsequent attempt. |
#19
IP: 47.142.134.119
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ANOTHER GUESS
Before you change the oil give us a reading on the dipstick. There may be no oil to change!
ex TRUE GRIT |
#20
IP: 98.117.4.37
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Fuel supply
When you test the fuel pump, make sure you test it as it is being operated during normal service. For example, if you have an oil pressure safety switch as required by the Coast Guard and you're bypassing it during your test, it could be bad and you wouldn't know it. If you have decent access to your carburetor, a good way to test the pump is to remove the main passage plug and use the pump to move a couple pints of fuel through the entire fuel system and out the bottom of the carburetor into a clean glass jar.
Still on the subject of the pump, is there a 5 amp fuse in the circuit from the positive of the coil to the pump? If not, and the pump is drawing higher than normal current from the positive terminal of the coil (to your observation that the pump is getting hot), it could be limiting the strength of your secondary discharge at the plugs. Don |
The Following User Says Thank You to Don Moyer For This Useful Post: | ||
Sam (09-01-2020) |
#21
IP: 98.117.4.37
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Fuel supply
Sorry; I muddled a point in my last post. It's very normal to bypass the oil pressure safety switch when troubleshooting a fuel pump. What I should have said is that if that's what you did, leave the oil safety switch bypassed and try to start the engine. If the engine operates normally, the oil pressure safety switch is your problem and you'll need to replace it. Don
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#22
IP: 67.168.58.141
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If the coil gets hot the engine will shut down. The standard install is with the coil hanging on a bolt on the block where it gets very hot.
I had problems where the engine would run about 10 mins, then shut down. I bought one of Don's high power coils and moved it over to a nearby bulkhead and haven't had any more problems. Jack |
#23
IP: 71.215.10.30
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I am not sure where this thread is at currently, but I will tell you how I determine if fuel is not getting to the carb.
I take an outboard can and put it on the deck. Thru the open port light I run the hose to the carb. Pump the bulb and poof you have gas to the carb. I ran it this was for 20 miles at 2000 rpm and 6 knots. My fuel pump was intermittent and made me crazy. The other way I initially tried was just filling a one gallon jug and setting that higher then the engine. Put the hose in the jug and run it to the carb. (this was the only problem I ever had with the Atomic Four, in over 20 years!) |
#24
IP: 38.27.109.137
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Quote:
I think I calculated once that the gravity-feed fuel source would have to be something like 10 feet above the carb to match the pressure of the fuel pump, although I remember multiple posts reporting success at deck level. Bill Last edited by W2ET; 09-01-2020 at 04:06 AM. |
#25
IP: 71.215.10.30
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Quote:
I used gravity on woods cars and dune buggies. Many motorcycles used gravity feed. Generators and power equipment often use gravity. My antique outboards use gravity feed. |
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overheat, shutdown, thermostat |
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