253 running issues after top end overhaul

[Panama]

not yet. at work till next thursday so cant touch the car.

boss at work reckons it could be that the carb has been on a car before and could have been overtightened at some point making the top of the housing warp and giving it a vacuum leak.

i can see that cylinder 1 is on the rock when the timing mark on the harmonic balancer is on the timing mark at tdc.


i need to wait for a kit from the us for the other quaddy i have already stripped cleaned and which came off a running 308 vh. i think that may fix my problem.

 

[Panama]

still no go. manufactured an aluminium plate to seal the idle galleries that the manifold left exposed (?!?!??) and new fuel pump.

loosely attached a tacho, and this thing wont idle below 2200 rpm. also once it cuts out, even if you full throttle it or pump the accel pum it wont restart.

since i made that plate and fitted it, i've been able to get the the timing to between the fuel pump bolt and the timing mark plate, so i'd guess about 20 degrees.

i just cant lower the idle or reduce the rediculous amount of advance this thing needs to keep running.

is there an easier way to see if the cam is a tooth out or whatever than taking the timing cover off? it's rocking as the mark hits 0degrees on the h/balancer at the timing marks.

 

[DAKSTER]

Move the dizzy around one tooth and see if it runs better. If it doesnt, see if going the other direction helps. Much easier than taking things apart again.

Its real easy to be one tooth out if you think about it.. only needs to be a couple mm to left or right to slide down the cog on the wrong side of the tooth.

 

[Glyn]

still no go. manufactured an aluminium plate to seal the idle galleries that the manifold left exposed (?!?!??) and new fuel pump.

loosely attached a tacho, and this thing wont idle below 2200 rpm. also once it cuts out, even if you full throttle it or pump the accel pum it wont restart.

since i made that plate and fitted it, i've been able to get the the timing to between the fuel pump bolt and the timing mark plate, so i'd guess about 20 degrees.

i just cant lower the idle or reduce the rediculous amount of advance this thing needs to keep running.

is there an easier way to see if the cam is a tooth out or whatever than taking the timing cover off? it's rocking as the mark hits 0degrees on the h/balancer at the timing marks.

Just because its rocking at TDC doesn't mean much as the duration of the valve overlap (rocking) is enough that the camshaft timing could be miles out and it would still have both valves slightly open at TDC.

If I were you I would bite the bullet and take out the radiator and harmonic balancer (if you can call the holden one that) and check the marks on the sprockets on the crankshaft and camshaft. The marks should be in line with the centres of the crank and cam if my memory is OK.

If not you need to revolve the crank sprocket on the chain till it does. Make sure the chain is not to slack. If it is or its a single row chain throw it out and fit a new one.

If I were a betting man I would say your a tooth or two to advanced in cam timing. If it were retarded it would run but just be gutless

 

[tigervh]

Sounds very much like the old 9 links on the timing chain trick to me.

Did you line up the marks on the sprockets with each other or;

did you position them to the right hand side of the motor as you are looking at it and count 9 links between the marks?

If there is not 9 links between them the cam timing will be out but the engine will still start, Just!

Many mechanics have been left with eqq on their faces from this quirk over the years.