1971 3400 3cyl gasser help

greeneri

New User
Any help would be appreciated.

Installed a rebuilt head on my 3400 3cyl gasser and can't get it to fire up. I gapped the 405 plugs to .025 and have spark to them. I've got the fuel line gravity fed for the time being, just to reduce one more problem although the tractor won't fire even with starter fluid sprayed right into the intake manifold. I adjusted the valve lash to .015 intake and .018 exhaust, but I'm not sure if I'm missing something. Has anyone got anything for me to go on? What is the best way to adjust the valve clearance? The way I did it was to bar the engine over until the distributer points just close at each of the three flat spots, and then gap the lash. Am I on the right track. The service manual doesn't give much info on how to go about adjusting the valves. I'm just about out of ideas, so any help would be appreciated. Thanks.
 
greeneri
To double check intake valve open intake valve closed set valves on that cylinder dist points just opening .Is dist rotor pointing to that wire in cap.Were rocker arms pitted at valve contact?Traper
 
I adjusted both intake and exhaust valves just as the points closed. The rotor is pointing to the distributor contacts, but I have a "boot-camp" question. The firing order is 1-2-3, with cylinder no. 1 at the front or closest to the radiator, right? I double checked the coil, and have plenty of spark (got lit up a few times) right to the spark plugs. The rocker arms looked to be in fine shape. No wear to speak of and no pitting. I'm thinking that I am missing the basics.
 
Greeeneri,
You may have over tightened the valves so that you are not getting compression. Or, your timing may be off. A rough check would be to put a thumb over the spark plug hole and crank the engine while watching the grounded plug. The compression should blow your thumb off the hole just as you see the plug spark.
 
greeneri
Nomber 1 at rad.Plan (b)pullplugs squirt oil in plug holes rotate engine.Spray carb cleaner in each plug hole install plugs see if it fires (dont life start fluid too hard on pistons)or just try to start it full choke(is choke closing all the way)traper
 

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