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5k rpm limit and cutting out


peteretep

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I am having a couple of problems with my escort.

1st is that it is very hard to get above 5000rpm, there are no noises or other indicators other than it really struggles to get any higher, of which I have forced in to about 5500.

2nd problem is that when you load up the engine quite alot it kind of cuts out, for example if you go hooning around a corner; after less than 2 seconds all power will be lost ( if you keep your foot on the floor it will be at a crawling pace) until you take your foot off the floor then allow the revs to return to normal then you can keep going. In saying that though after I pushed it harder the engine even cut out and wouldn't start for 30 mins.

I have tried bypassing the alarm but that did nothing. I have also taken the car on a dyno and it leaned out at higher rpm which would indicate that I need larger jets but cutting out just when under load indicates to me that the jets are not really to blame considering I haven't heard any pinking. I have a feelin that the problem is electrical because it would take longer to empty the carb bowls but I'm not sure what to check

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First it was only around corners but happens if you try do a skid or accelerate quick

Yeah electric fuel pump but I would have bought that the fuel in the bowls would have lasted longer than 1 or 2 seconds.

Also just opened up the carbs and nothing was dirty

Edit: just took it for a drive to get more gas ( make sure it wasn't lack of gas causing my problem) and when driving back in a straight line not hard accel at all it cut out at almost exactly 5000 so took my foot off the gas and it continued on like normal...

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I'm thinking fuel pump 1st and and ignition system ignitor/coil/distributor 2nd

you have those bike carbs which don't have as big of a fuel bowl as a weber or holley type carb. the other thing would be fuel pressure too much/too little.

so. measure pump flow, disconnect fuel line to carbs and run pump into a bucket/vessel and time it then workout the flowrate. if you can get a fuel pressure gauge on it - although you probably wont be bale to have that such that you could read it while driving.

ignition system maybe a little harder to troubleshoot if it works normally but only breaks down when it gets do 5000rpm. you might need to take it to some auto sparky who has a test rig thingie or something - unless someone wiser than me in the ways of lucas smoke engineering can offer another option.

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took it for a drive to get more gas ( make sure it wasn't lack of gas causing my problem) and when driving back in a straight line not hard accel at all it cut out at almost exactly 5000 so took my foot off the gas and it continued on like normal...

Do you mean that after you lifted and re-applied the throttle the engine went past 5krpm?

Yes = Float bowl setting

No = Points bounce

A standard Kent 1600 probably doesn't do much past about 5,000rpm anyway so don't expect it to perform like a modern alloy head twincam

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I took my foot off the gas and let the car slow down to 3000 then put my foot back down and continued like normal. It was a jolt when it hit 5000 rather than a feeling of running lean which to me indicates loss of spark.

Idle, starting and revving with no load is as expected and normal with no other signs.

The engine has a BCF2 cam which is said to be good for 6000rpm, and I certainly took my old 1300 engine past 5000

I'll have a look at the pump and bowls

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I have looked at the bowls and the pump. The bowls were all equal and I think that the angle that they sit on in my car put more fuel in the bowl than the standard setup, it was well above the main jet suction at any rate. The fuel pump did 29 gph at 2.9 psi which is almost the pumps max stated free flow rate so I can't really fault that

UJ I have an electronic Subaru dizzy so I won't be getting points bounce

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prob not the problem but i had a similar prob with my 1600 it erked the shit out of me . turns out i had a perishes vacuum advance line and would seal somtimes , not others and would never seal above about 4k .

just somthing to check i spose? .

but being electric it might not have a vacuum advance

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Well I guess a good question is whether or not vac advance is required and if it's not hooked up will it lower the total advance? I have searched the net but I can't find good info on it, my understanding was that vac advance didn't affect total advance but I might be wrong.

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Have you got a timing light - connect it on to an HT lead and tape the timing light to your windsreen with the light end visible from the drivers seat - go for a drive and see if the timing light cuts out when it stalls - this should isolate it to spark or fuel - it sounds like fuel to me but may as well confirm it..

I may be remembering shit but I do recall reading something about motorcycle engines having issues in 4 wheeled vehicles cos motorcycle engines are designed to be leant over when cornering and as such keep the fuel in the bottom of the float bowl.

In a 4 wheeled vehicle the carbs would stay essentially flat and the g-forces would slosh the fuel up the sides of the carb and possibly away from the mainjet port.. its chucking an out there theory out there so feel free to ignore it..

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Carbed Peugeots do all of this hardout when the floats get old and heavy from absorbing fuel over their life time. My 309 used to run out of fuel going around corners and under brisk acceleration and times of high fuel demand (e.g. WOT & 5000+ RPM). 'Twas lol/shit.

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I have looked at the bowls and the pump. The bowls were all equal and I think that the angle that they sit on in my car put more fuel in the bowl than the standard setup, it was well above the main jet suction at any rate. The fuel pump did 29 gph at 2.9 psi which is almost the pumps max stated free flow rate so I can't really fault that

UJ I have an electronic Subaru dizzy so I won't be getting points bounce

so ~1.8L/min if you break the fuel line at the carbs?

ok that should be enough. so probably not the fuel pump.

have you got a timing light? what are the plugs like?

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After reading a bit more about symptoms of jets that are too small, it appears that cutting out etc is a sign, so once I get my car back from the suspension guys I'm going to take it back to the dyno and start messing around with the jets. I didn't realize that small jets could make the engine perform like it has

On a side note I read that if you have jets that are too small you can test it by driving along at near full throttle then take your foot off the gas slightly and if the car goes faster then your jets are too small, called the roll off test I think

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Thats a point. You would think so but it has been getting worse. At 5k under full load it was showing 15:1 and it wouldn't go any further but it wasn't cutting out at that stage and now it is...

After checking the fuel pump and the floats I can't see how I couldn't be keeping up with fuel or even running low at the jets, as soon as it needs it, it will be there. Especially when you drop the clutch and it does it, it's just way too fast for the bowls to run dry. Also, im pretty happy that the floats have not absorbed fuel.

Maybe I'll try the timing gun taped to the bonnet and to see if it's electrical, maybe something inside the dizzy is limiting it??

Edit: if I take it back to the dyno then at least they can get one thing out of the way

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