The Stovebolt Site Forums The Shop Area Engine Shop engine breaking up before shift

I was hauling some gravel again this weekend with my 53 2ton. when I am on the road empty the truck runs like a dream, but when I have a few yards of gravel on it and I am getting ot of the pit in low and high range on the road it seems like it is loosing the spark as I bring up the rpm to shift. could I be getting to much spark advance on the Distributor?

Might be a bad coil - sounds like symptoms I had once and coil fixed it.

I agree with "chuckthetruck". Sounds "electrical" to me on first pass. How long since new plugs and plug wires?

I only purchased the truck about 3 months ago from a retired farmer he said it had a complete tune up in 2003 at the garage up the road everything looks new I will check the coil as it is a bit of a pig to start when it is hot

pig to start when hot? how..??? if it cranks hard hot sounds like timing is to far advanced maybe....

When it gets hot even after running empty to the pit you can crank it till the battery is almost toast. if I give it a little push with the bobcat it will fire right up no problem. temp on the guage is about 110. wich cyl is number one and where are the timing marks on a 235.

http://community.webshots.com/photo/551730017/2898006040093477578zbuuBZ

no.1 front of engine,,timing in hole in bell housing just above starter,,marks on engine side of flywheel,,hard to find and read,,,take engine to no.1 tdc and look as you roll over by hand,,if area dirty use brake clean and air to locate,,if can,t locate use vacum gauge to set timing...doc

My '54 Suburban was having the same problem: hesitation only when accelerating at high RPMs (under load, near the shift-point). After checking just about everything (including swapping out distributors, points, Pertronix unit, carburetor, coil, and adjusting timing from +/- 10 degrees from TDC), I found a very minor vacuum leak in the vacuum side of the dual-action pump (I had already isolated a minor vacuum leak in the wiper motor).

I disconnected and then plugged the intake manifold vacuum port and the truck now runs like a top (and it starts more quickly at all temperatures).

Check to make sure when the tune up was done they did not loose the points return spring. If there is only a thin brass strap the spring tension will not be enough and the points will float at higher RPMs.

Hey fellas just wanted to say thanks for all the great ideas it torned out to be a small vacum leak in the wiper unit and a small leak in the two speed axle vacum line THANKS