Post head-retorque blues - stumbles under load.....

[rogerh113]

Hello,

Well, fired up the 113 after the head re-torque and valve adjustment.   Idle was very nice and smooth (like before the process), but after the car warmed up a bit, I started down the street, and the car is stumbling under load as I accelerate (car drove well prior to the 'service').   When I got back to the garage, the car was back idling just fine......

I figured I had accidentally detached the vacuum advance hose, but on inspection it seems fine.  I did pull the distributor cap to add a few drops of oil to the center drive shaft cotton wick and put a few drops in the side oiler on the distributor.  The engine is a 250 low compression engine.  Any suggestions??  Could the engine have been sufficiently leaky for the fuel mixture to be affected by the re-torque??

I also pulled the valve cover again just to check for the left rag or broken spring, but all looks great in there......

[ja17]

Hello Roger,

Check to see that the spark plug wire ends are securely attached to the wires. These wires and ends can be easily checked with an ohm meter.

Another guess would be that you somehow got the linkages out of sync. Be certain that the two 10 mm cone shaped nuts on the cross over rod are mounted with the cones down.  These look like lock nuts but are not. Often times they are installed incorrectly with the cone side out.  The cone shape of these nuts, when installed correctly will precisely center the linkage cross over rod so that the sync between the intake and IP will remain correct.

[rogerh113]

Thanks for the suggestions. 

I did check the wires already and they are good.

The linkages I will go over tomorrow.  Turns out that I had the linkages carefully adjusted before, but the bolts were flat side in.  Having read the valve adjust post, I did install the bolts correctly this time, and so may have thrown the linkages out by installing them correctly......

Thanks -- Roger

[rogerh113]

Hello,

Went through the linkage, and it was pretty much fine.  The link to the block pivot was a bit long, but that was all that needed to be adjusted - link to IP correct length, with IP link and butterfly link engaging at the same time.

Same symptoms.  Idle is good.  Revving at standstill pretty much ok, with a wee bit of hesitation on the way up, but under load it completely falls apart.  Significant stumbling, reluctant to rev (or even start to rev), and then idle takes a while to re-establish smoothly.  At idle I did pull the vacuum advance hose at the manifold, and there was a noticeable rev change, so I assume that the vacuum advance is working (at least to some extent).

Any ideas or suggestions.....

Regards -- Roger

[rogerh113]

Well, after the last email I went back out.  Since I had run the car for a while in the prior attempt, it occurred to check hot performance.  Turns out the car ran fine - went around the block a few times with no issues.  Must have messed up one of the cold-start components, so off on that witch-hunt tomorrow.

Thanks -- Roger