Engine trouble

[SandmanMuscle]

I have a 186(202 head) that when it hits 70k's+ it "chokes out", for lack of a better description. I can drive around all day aslong as I dont exceed 70k's. If I do it will start to "choke" and eventually stalls. Starts right back up again though. Going uphill it sometimes happens at a lower speed.

I can full throttle it through 1st and 2nd but if I hit 70k's or higher in 3rd or 4th this little choo choo just cant. I don't think it is miss firing, its not back firing. It just losses power once I go over 70k's.

Dont think its the dizzy, spark plugs should be sweet. I've checked the bible and it doesn't have the exact symptoms I have so not sure what the go is.

Anyone had anything similar?

[wbute]

Air filter blocked? Fuel filter blocked? Fuel line blocked? Timing out? Carby warn out?

[V6HQUTE]

my paddock basher had a little screen blocked up where the fuel line screws in, mainly because i was using a bit of rubber hose to extend the fuel line, and well wasnt made for fuel i couldnt even get to 70, went allrigh but once it got to jogging pace she stalled suprisied me it still ran i reckon half the rubber hose was in the screen, this was on a 202 with varajet

[Taily]

Sounds fuel related.

Carby: possible sticky needle and seat - sticking partially closed. Seen it but not common on strommies. While you're there check the nuts that bolt the carb to the manifold are firm and the base gasket hasn't sucked-in anywhere.

Fuel Filter: More than likely the culprit if one fitted - blocked.

Other probable culprit: worn out fuel pump.

Fuel lines: when changing the fuel filter try (very very gently) blowing some (not much) compressed air back towards the tank. I say gently as I cannot remember if they had a sock on the pick-up in the tank. Make sure you remove the fuel cap so as not to damage any of the breather lines and fittings and also listen for the bubbles in the tank.

While you're there check your manifold gasket by running the engine at idle and spraying agentle mist (away from the alternator and definately not after a 10km drive with a hot exhaust manifold) of something like WD40 etc around where the manifold mates to the cylinder head and around any vac pick-ups such as brake booster etc. If the idle changes you have a vaccuum leak to fix. Be careful though. Some people suggest using water for that test for good reason....

Try a run without the air filter also to see if that is an issue.

Possible but unlikely the cam gear has shed a tooth.

Regards,

Dave

[SandmanMuscle]

Not air filter, not fuel line, timing is sweet, could be fuel filter. It has one before the pump and one after, don't know if I need both. And then it could be the carby. Ill start with some new filters.

Edit: Thanks Dave, I will give the carby a look over, it wasn't long ago that I put new gaskets on it, so I'm hoping thats not it. Will give your advice a go cheers.

[adam perth]

check carby needle and seat and check points if that fails.

[wbute]

I back a carby problem if it was the last thing worked on. Fuel filter after pump is a bad idea as far as I know. They are a low pressure thing and it just increases the chance of trouble. The filter has already done the filtering before the pump.

[HK1837]

Sounds very much like fuel filter to me.

[wbute]

The other problem could be that 2 cylinders have fallen off?

[HK1837]

That is a Starfire 4 (with 2 x cylinder lopped off)!