200 won't crank fast enought to start

[Anonymous]

Hi all:

I'm in the process of rebuilding my 200 (just finished, I thought). I went to turn it over for the first time, and am having problems with the engine cranking entirely.

It only cranks about 1/8 of a rotation and dies out. I let off and try again and get the same results. It won't consistently and repeatedly crank. I have tried a new battery with the same results. I just think the engine won't crank fast enough to ignite. I removed all the spark plugs and tried to see if it was a compression issue and it still won't crank quickly. That leads me to think either the starter is going bad (easy fix) or worse there are problems with my build up. I am beginning to think that something went wrong with my build and that either the clearances aren't right with the crankshaft seating or bearings are too tight.

I do remember it being a bit difficult to spin the engine over by hand after installing the pistons, crank, cam, and timing set but I just thought I was imagining it since it was my first entire rebuild. Nothing hung up or seemed out of place, it was just hard to turn over by hand.

Thoughts? Suggestions?

Thanks.

 

[Bort62]

Well, I think you have nailed two of the three possibilities.

The third is that you have a poor connection between the battery and the starter.

I forget if these motors use Chamfered bearings or not, but if they do - putting them in backwars can cause this.

 

[mustang6]

Did you measure the bearing clearances (with a micrometer or plasti-gauge) during assembly? Also did you lube everything well so the bearings are not trying to spin dry?

I'd work on the starter/battery/connections angle first, but I am suspicious of the difficulty you had turning it over by hand before the head was installed. Obviously there is going to be some resistance with friction on the new bearings, rings, seals, etc., but I would estimate it taking only about 15-25 ft/lbs of torque on the crankshaft nut to turn over a well lubed, fresh 200 shortblock (no head or compression).

 

[Mercury Mike]

Yeah, I think you installed the bearings backwards. On the rod caps, number towards the crank. If you used some good assembly lube, it should spin over like nothin'. If it only goes an 8th of the way, then it might be starter related. Swap out the starter, after checking all connections. =D

 

[HARVEY LIGHT]

I had the same problem when rebuilding a C***Y II a few years back. It seems I hadn't checked the ring clearance and they were too tight which caused them to bind somewhat in the bores. That might also be your problem. I know it's a bugger to tear it back down and measure these but you might give that a thought if the other ideas don't pan out.

 

[rbohm]

8) start by having the battery load tested, as well as having the starter tested. then check the battery cables for a proper connection, as well as corrosion in the cable itself. make sure you have a good ground between the engine and the chassis, as well as the battery and the engine. once these things have been checked, and any corrections made, then you can think internal problems.

 

[Anonymous]

One other thing to mention (not sure if it helps or is just a coincidence), I took note that the ground cable coming off of the battery to the engine block was getting very warm to the touch just after a few cranks during this process as well. Would the cable heat up in just a few seconds of cranking or could this be an electrical issue?

Just thought of it since rbohm mentioned having a good ground.

 

[pedal2themetal45]

eather an electric prob or the motor is so hard to turn over its drawing to much power and burning the starter out.

 

[pedal2themetal45]

pull the plugs and try to spin it by have it should turn over fairly easy.

 

[cfmustang]

Timing way too far advanced? I know when I had mine too far, it was having difficulty turning over...

 

[Anonymous]

OK, thank you all for the advice. After hearing your input and talking to a few of my other friends, I'm going to pull the engine and investigate where things went wrong.

It sounds like the engine should turn over pretty easily by hand with no head or compression, but it didn't turn over all that easily from what I remember. I had a 2 ft breaker bar with a socket on and it was definitely a two handed job to turn the crank before I put the head on it (probably about 50-70 ftlbs). I just assumed that it would loosen up after I got it started and things got seated.

 

[wallaka]

Yeah there'll be a little friction, enough that it will be easier to put a bar on it to turn, but it should still be doable by hand.

 

[addo]

There should be a good degree of friction in a brand new motor, I've heard of others where the old starter wasn't up to it. You have fresh rings in a comparatively rough bore, for starters.

If clearances weren't gauged, then they should be. It'll take some care to ensure the seats don't get oil between them and the shells.

 

[jamyers]

Hate to say it, but I'd pull it back out and doublecheck the bearing clearances and the ring gaps - sounds like something is too tight.

I'd do it before I tried any more cranking, just because you can really cause some damage that way.

The warm wiring is likely because of all the current being drawn to try and crank the motor over.

 

[Anonymous]

Thanks for all the advice. I pulled the engine last night but that's all the further I got with it. Looks like a Saturday project. I may be back with more questions depending on what I find out.