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Just Can't Get The Engine To Rev


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#1 Tonylamb

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Posted 18 August 2019 - 08:48 PM

Got my engine back and in the car in about 6 hours brilliant. starts OK but doesn't want to idle then took her up the road. simply won't rev over 3500. If you put your foot on the accelerator at all it just dies and stalls. you can feather the throttle to move along at 50 or so but any accelleration at all and the engine just bogs down completely. I've checked the static timing its between 6 and 8 degrees. used the colour tune and re set the idle. it doesn't seem to want to idle any sense either. Really odd it was running fine when it went away but just rattled. now it doesn't rattle but won't run any sense at all. I can't seem to find any air leaks. I have a Vizarded HIF 44 carb with pancake filter. I do have a bit of a racy cam in it. Its a 1275 bored out to 1361. i checked the oil in the dashpot and refilled it with 3 in 1. The carb is the same as before and untouched and it ran fine back then?

i'm sure this must be something to do with timing but that seems to be set fine. any help much appreciated.

#2 ukcooper

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Posted 18 August 2019 - 08:56 PM

wrong needle try a BDL will be rich but send it a rolling road and leave it alone co not mess with any thing after unless you want roll/road it again



#3 unburntfuelinthemorning

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Posted 19 August 2019 - 06:44 AM

Cam timing set properly?

 

Major air intake leak?



#4 Tonylamb

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Posted 20 August 2019 - 06:07 AM

Took the carb off and reset the float height to make sure. The needle and assembly seems to move freely. The filled with 3 in 1 oil. Shoukd the piston that goes into the black screw on cap be fixed in a line of does it flex from side to side. I didnt have time to run the engine but will see if that has made any difference.

#5 imack

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Posted 20 August 2019 - 08:02 AM

The damper piston floats on the shaft

#6 Tonylamb

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Posted 20 August 2019 - 08:25 PM

Car is actually worse now so it's not float chamber I've noticed in the distributor that the cam on the points slides up and down. At some point (excuse the pun) the actual points are barely touching. I'll try and post a video

#7 Tonylamb

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Posted 20 August 2019 - 09:17 PM

i've tried to post a picture but can't. the red cam on the points is moving up and down the rotating shaft in the distributor its an Aldon. Is that normal i wonder if when it rises up the spark goes completely and that is the problem rather than fuel.

#8 Tonylamb

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Posted 21 August 2019 - 09:24 PM

The points were either bent or faulty so I put another set on the car. i've reset the valve gaps and set the carb jet level with the top then backed off by two turns. fiddled with the idle. But something is still very wrong. its much much better in first and second and goes like the preverbials. but in third and fourth it bogs down under load or accelleration. It feels like some form of fuel starvation. The carb pot has 3 in 1 oil in it. I reset the float level in the carb and the piston rises and falls without sticking. The fuel pump is exactly the same as before as is the fuel regulator and I had no problems like this. the engine rattled in the transmission which is why I took it out. So whilst nothing has changed in the fuel supply I don't think it can be that.

Where do I start.? I have electronic points on the way and will fit them tomorrow I just think they eliminate a number of stutters etc from the rev range. I don't know perhaps the piston is sticking but its hard to tell from the drivers seat.

I also spent some time with the engine at idle spraying brake cleaner around the manifold gaskets etc. didn't have any noticeable change in engine note at any time. I suppose an air leak would be worse at higher revs so less noticeable at idle but you should be able to notice.

Really stumped and could do with some ideas.

#9 unburntfuelinthemorning

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Posted 22 August 2019 - 07:03 AM

Have you tried a compression test?



#10 Tonylamb

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Posted 22 August 2019 - 01:39 PM

its a brand new rebuilt engine.

#11 Tonylamb

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Posted 22 August 2019 - 01:43 PM

It also ran absolutely fine before it went off to have the transmission sorted. So the problem is something that has happened when I've put it back this time? The carb is the same the fuel pump and regulator are the same. The needle is the same. we did knock the distributor cap off when installign the engine but only gently. The points were a bit off so I replaced them. The valve gaps are spot on at 15 thousanths. it can only be two things, fuel and therefore carb or ignition and therefore distributor? As I've said I can't find any air leaks.

Perhaps I should change the exhaust/inlet gasket just to make sure. But an air leak bad enough to cause this problem would be very easy to spot or hear. If I could get a list of things that would cause boggin down it might help.

#12 Tones61

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Posted 22 August 2019 - 03:13 PM

condenser gone iffy ? :gimme:



#13 Tonylamb

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Posted 22 August 2019 - 03:58 PM

nope just put a new set of points and a new condensor on it. Its either timing or fuel. I've had contradictory reports. One mechanic mate thinks its more likely fuel or lack of. Another said that HIF44 is generally rubbish but that this sounds like like timing or distribution. I'm wondering if the company that brought the engine back have wacked the distributor and bent something. It was odd how that original set of points were running up the cam. But then it wouldnt run right further up the rev range which it seems to do.




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