1.7 Rebuild First Start Up Advice, 1.7 Start Up on stand Options

[Robroe]

Have 73 1.7 bought in pieces. Engine has been rebuilt and ‘souped up’ however I don’t know what internals were installed. New crank, cam, pistons, rods and heads. but I don’t know which ones. Weber 44 idf carbs. Never had oil in it and been stored unstarted for 10 yrs in climate control. I’ve added oil by slow dripping 2 quarts through the oil pressure sensor hole. Oil dripped out of the rockers so I’m pretty sure it got some oil as pre lube. It’s on a home built test stand with the transmission mounted with the starter.

I’m trying to turn the engine over by hand with the plugs out. Have squirted oil in each plug hole. I’m able to turn the engine by hand about 45 degrees and it gets harder to spin so can’t go any further. Would it be a good idea to pull the rocker arms to see if the builder installed some wild cam without checking valve/piston clearance? It doesn’t feel like internals are hitting each other but who knows? Would hate to pull the heads if I don’t have to. Any thoughts before I break something?

Rob Roe
Newbie

[930cabman]

Have 73 1.7 bought in pieces. Engine has been rebuilt and ‘souped up’ however I don’t know what internals were installed. New crank, cam, pistons, rods and heads. but I don’t know which ones. Weber 44 idf carbs. Never had oil in it and been stored unstarted for 10 yrs in climate control. I’ve added oil by slow dripping 2 quarts through the oil pressure sensor hole. Oil dripped out of the rockers so I’m pretty sure it got some oil as pre lube. It’s on a home built test stand with the transmission mounted with the starter.

I’m trying to turn the engine over by hand with the plugs out. Have squirted oil in each plug hole. I’m able to turn the engine by hand about 45 degrees and it gets harder to spin so can’t go any further. Would it be a good idea to pull the rocker arms to see if the builder installed some wild cam without checking valve/piston clearance? It doesn’t feel like internals are hitting each other but who knows? Would hate to pull the heads if I don’t have to. Any thoughts before I break something?

Rob Roe
Newbie

(IMG:style_emoticons/default/welcome.png)

If you are unable to get a full rotation of the crank somewhat easily, start dis assembling her. Or try the starter to spin it over. If you are able to get her to spin, connect an oil pressure gauge and see if she will pump up some oil pressure.

Might get lucky (IMG:style_emoticons/default/sawzall-smiley.gif)

[Superhawk996]

. . . Or try the starter to spin it over. If you are able to get her to spin, connect an oil pressure gauge and see if she will pump up some oil pressure.

Might get lucky (IMG:style_emoticons/default/sawzall-smiley.gif)

I would strongly advise against this. You will not get lucky. The starter exerts a lot of torque on the crankshaft. The starter is fully capable of bending valves. I don’t know the gear ratio between starter and ring gear off the top of my head but it’s probably about a 10:1 mechanical advantage.

If you already have an interference that isn’t allowing you to rotate the crank - more mechanical advantage will only serve to break or bend things.

Without spark plugs the crank should rotate freely by hand, no exceptions.

Oil pressure has nothing to do with not being able to freely rotate the crank at this stage in the game. If the original builder didn’t apply assembly lube to the main bearings and the cam lobes, the damage would be done before the engine ever builds oil pressure by rotating it. And if that sort of negligence was causing a lack of hand rotation (I’ll guarantee it isn’t), that would be all the more reason to tear it down, find out what was done, and reassemble it correctly.