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Aq131a starts and runs well but cuts out when warm

markymark

New member
"Hi all, my engine starts fine

"Hi all, my engine starts fine and runs well but some times it cuts out as soon as it gets warm. other times i can run it for hours without a problem. Im told the carb is working properly, i have replace the condensor and coil but it happened again the other day. I'd appreciate any help and advice anyone can give me, Thanks Mark"
 
"Hi El Pescador thanks for you

"Hi El Pescador thanks for your response. The times its happened have been at idle out of gear and also in gear at very low revs. I havnt tested it at a higher rpm. This i will try when i go to the boat later this week. Its possible that it only happens when i start it from cold. It starts fine at a slightly higher rev, as the engine warms up i lower the rpm and put it in idle once it has warmed up. It will run fine for maybe another five to ten minute then just cuts out. Ive tried to start it straight away but it will continually turn over but will not fire. If i leave it for about 20 to 30 mins it will then start and run fine. On one occation this season it also started from cold and ran with out cutting out at all.
I checked all the plug gaps, they are all 0.7mm, reset the points to 0.40mm (not sure what the dwell angle is). Wound out the mixture screw on the carb two complete turns and set the idle to as close as i could get to 900rpms. Not too sure if the rev counter is accurate it was reading 1000 if i idle it any less it cuts out. I used the timing light and the timing was showing 5 degrees btdc so i advanced it to 6 degrees as it says in my manual. I left it running ok but it was warm so i will have to see what happens when i start it later this week. What do you think?
I have another problem with my out drive that i hope you can help me with. I have twin AQ 131a engines with 275d outdrives. When i select between fwd and rev there has always been a slight clunk from the engine /outdrive. Last time i took the boat out one of the selectors was so stiff that i had to use quite a bit of force to get it between forwards and reverse. When i did the clunk has now turned in to a loud bang. It seems like its seizing up or someting. How can i sort this out and can i do it while the boat is in the water? Thanks, Mark"
 
"Mark, here are a few hints:

"Mark, here are a few hints:

1) Your engine needs to be warm to run properly. Bring it up to operating temperature at fast idle. Then keep it between 1000-1500 RPM and make sure the idle mixture is adjusted properly in your carb. Then adjust the idle speed to specification (900-1000 RPM).

2) If your engine stalls when warm and does not restart, put the control lever at about 75% throttle and crank. Once you hear the engine starting, bring the control lever back to idle quickly.

3) If you are using mid grade gasoline, your engine will work better with the idle ignition timing set at 10º BTDC.

4) If you still have points and condenser in your distributor, get rid of them and install a Pertronix electronic ignition (#2842 is the correct one for your engine). You will get a better starting and much smoother idling. Do a search in the forum about this.

5) The loud bang in shifting could be due to the idle RPM being too high, so make sure they are set to 900-1000. Make also sure that the shift cable is adjusted correctly where attached to the shift mechanism in the outdrive."
 
"Hi El Pescador,
I started th


"Hi El Pescador,
I started the Engine yesterday and warmed it up at a fast idle when it reached its running temp i increased the revs to around 2300. It didnt cut out this time. I altered the timing to 10 degrees BTDC as you advised (Do i leave the Advance and Retarder tubes attached to the carb when adjusting the timing?).Because its been an intermittant fault time will tell if it has been resolved . I'll keep you posted on that one.
Im in the process of ordering the pertronix electronic ignition kits for both engines. They are difficult to get over here but the cost of buying two of them and paying for them to be shipped over from the U.S. is still less expensive that buying one set of the UK's equivilant.
The sticky and noisey gear shift is still there and the revs are now 900rpm. How do i adjust the the shift cable in the out drive and can it be done while the boat is in the water? I only have a Volvo penta aq131 workshop manual and it hasnt any info on how to adjust this. Thanks Mark"
 
"Mark, not sure what tubes att

"Mark, not sure what tubes attached to the carb you are talking about. As far as I remember, none of the AQ OHC engines has vacuum advance. The only two tubes that go to the carb are a the fuel delivery line and a plastic clear hose to divert fuel from the fuel pump in case of diaphragm rupture. Am I missing something here?

The shift mechanism needs to be adjusted with the boat out of the water. After you remove the shift gear cover, you will be able to locate cotter pin (40) and washer (41). By removing them you free the cube (39), which can be moved forward or aft by turning it clockwise or counterclockwise. By moving the cube aft it will engage in "forward" faster, and vice-versa. You have to find the happy point in which it takes the same throttle (or clutch) lever travel to engage (smoothly) when you shift from neutral to forward and when you shift from neutral to aft.

http://www.volvopentastore.com/INTERMEDIATE_HOUSING_DRIVE_275/dm/cart_id.2230834 72--session_id.244999644--store_id.366--view_id.324084

If you are going to take the boat out of the water, check the condition of the oil. If it has water, that does not help."
 
"Hi El Pescador, Thanks for yo

"Hi El Pescador, Thanks for your help so far. Im going to leave the gear selector work until i take the boat out of the water in the winter.
I havnt been able to get down to the boat since your last message but ive receive the Pertronix ignigtors that you recomended. The positive wiring is dependant on whether i have a ballast resitor fitted. Im not sure if i have. If i have its nowhere near the distributor or coil. There is some kind of resister on the cable coming fron the alternator. Could that be it?"
 
"Mark, get an ohm meter and me

"Mark, get an ohm meter and measure the resistance of the coil between the (+) and the (-). If it is around 3 ohm you don't have a ballast resistor (or should not have one) as the coil has an internal resistor. If the coil primary resistance measures around 1.5 ohm, then you should have a ballast resistor.

The normal installation of the Pertronix kits are red to the + of the coil and black to the -.

The resistor in the cable going to the alternator serves a different purpose, which is preventing backfeeding of the ignition coil. In other words, without that resistor the ignition coil would backfeed from the alternator exciter field coil and chances are that the engine would not stop when you turn the ignition key off."
 
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