along the lines of checking the fuel starvation possibility-pull the fuel tank pick up tubes and see that they are not plugged or that they do not have any holes in the pipe that would allow air to suck in if the fuel level was below the hole. I had this happen once and it took forever to find it. I believe a tank baffle had gotten loose and over time rubbed a hole in the pick up tube. These pick up tubes also have a check valve in them usally at the outlet. I have found them to stick shut also. Hal ----- Original Message ----- From: "waterguy" <[email protected]> To: "UnifliteWorld" <[email protected]> Sent: Tuesday, June 16, 2009 6:34:16 PM GMT -08:00 US/Canada Pacific Subject: [UnifliteWorld] Re: engine problem on 32ss
So you have an engine that works fine at high rpms while unloaded, but won't rev up under load. First, I assume engine timing is normal, and that all ignition parts are in good condition (you didn't say if you have electronic ignition or points and condenser). Be sure that stuff is okay and the plugs are relatively new. If all that checks out, look for a weak spark. Using an insulated pliers, pull off one of the spark plug leads, start the engine and hold the lead near a good ground on your engine, away from the carburetor, fuel lines or fuel pump. You should see a strong, bluish- white spark arc across the gap. You might need to use an extra spark plug inserted in the plug lead sheath, then ground the plug to the block. There are also tools that you remove the plug lead, attach the tool to the top of the plug, and attach the lead to the top of the tool - inside the tool is an arc between two electrodes that will show you the strength of your spark. Sometimes an ignition coil can be weak - just strong enough to generate a spark in an unloaded engine but not strong enough to jump the gap on a loaded engine. The next thing I would check is the mechanical advance on your distributor. Hook up a timing light to no.1 spark lead, position yourself somewhere that you can shine the light on the timing marks and crank pulley, but be where you won't get caught in spinning belts. If you're in the engine compartment, wear ear protection. With the timing light going, rev the engine up and make sure the timing mark on the pulley disappears over the horizon. If you have an advance timing light (has a dial on the back), you can twist the dial as the engine revs up to see how far the timing advances. Overall, you want around 30 degrees mechanical advance; check the manufacturer specs for the actual amount. If the timing doesn't advance, the engine won't rev under load (although it shouldn't rev well unloaded, either, which is why this is the second thing I'd have you check). Finally, if the timing and advance check out, suspect a fuel starvation issue. Could be clogged filters, fuel pump not putting out rated capacity, sticking carburetor float needle, or gummed-up carburetor passages. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "UnifliteWorld" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/UnifliteWorld?hl=en -~----------~----~----~----~------~----~------~--~---
