1600 tp not starting

[Dean]

Just fitted my rebuilt 1600 tp engine but it wont start.

It has new 1600 mahle b&p's
it has fired up once and was really flat.

I rechecked the timing and it is right. I've replaced the new cap and arm for a known working one but now it just turns over with irregular spped and won't start at all.

Any ideas?

 

[noddy]

Done the basic fuel spark at plug, leads in correct order, rotor arm on dissy shaft ok (had this one myself engine would not start took ages to find I had not put the rotor onto the dissy shaft correctly rotor was staying still and shaft spun underneath).

Checked valve gaps and that push rods are seated ok, drive dog on dissy in slot on gear correctly?

If yo have a good spark at the plugs, try pouring some fuel down the carb if it runs ok it will probably be a problem with the carb or pump.

 

[Dean]

We've now gone to the point where the engine no longer turns, either by starter or by bump in gear.

So it's either bottom end seized or the flywheel is jammed on the gearbox mountings.

Any other ideas?

 

[noddy]

Did you fit the pistons the right way round, did it turn by hand before you fitted it?

 

[james_stan]

Total rebuild or B&Ps upwards ?

 

[VWAIRCOOLED]

If you've put new bearings and/or an oil pump in it,the crank could be running dry.Make sure the oil is right up to the max with a new oil pump.Try turning it over with a socket on a long bar on the front pulley bolt.If you get it turning then remove the oil pressure switch and turn the engine until oil comes out,refit the switch and crank it over.It should loosen off when the oil gets circulating if thats the problem.Did you have the flywheel off at all? If so did you set the end float properly with the correct shims?

It may be worth taking the starter motor out first to check that nothing is jammed in the flywheel and check the brass starter motor bush is fitted and not worn out.

 

[Dean]

Thanks for the replies the inspection took place as below.

Stripped the engine bit by bit tonight and discovered the problem.

Right from the start when i rebuilt the top end (b&p's upward) i checked everything was ok and moved freely. It was and did.

I took the engine apart bit by bit and tested ever step of the way.

The diagnosis is that at full stroke the con rods jam into the case and seize the motor solid. I can then wind the motor back until the previous full stroke and it does it there too.

Confused? me too as this engine was running (smoking and tapping on no.3) in my late bay before the rebuild.

Nothing was touched on the bottom end. I even replaced the rings recessed in the heads even though it makes the heads sit a tad proud from the barrell casings.

So now i'm left with a case that was working but is now suffereing a fault without knowing where or how it materialsed and where to go with it from here.

Any ideas?

 

[noddy]

How long have you had this engine? (do you know its history have you run it for a few months)

Are the conrods in upside down, from memory they are supposed to go on the crank with the small dash on the side pointing up.
Only other thing I can think of is, the cranks bent, but I would have thought this would be noticeable when you roll it over by hand.

 

[Dean]

This has me stumped so i am going to put it aside while i sort another one to get back on the road. There were no obvious bottom end issues when i was running it before. The tapping was a lot of piston slap on no.3 cylinder. Apart from that it was sweet.

Once i'm back on the road i'll strip this bugger down and see whats going on.

Thanks

 

[VWAIRCOOLED]

Sounds like a valve is hitting a piston,did you check and set the valve clearances in the correct positions? The fact it did start and run flat could be a valve wasn't shutting properly.Are the spark plugs the right ones,not extra long reach? Look for evidence of contact on the piston crowns.

How far have you stripped the engine down at the moment?

How did you tell the con rods where hitting against the case? This seems strange,even with no barrels off there is plenty of clearance for the rods?

 

[K@rlos]

We had a 9L Cummins truck engine at work which a fitter and his appentice rebuilt, same thing REALLY slow to turn over, another fitter stripped it again and it turns out that the appentice had seriously over tightned the crank shell journals therefore it locked the crank up :roll:

 

[Dean]

I thought that maybe i tightened the heads too tight and somehow pressed the cases together but the crankshaft still sticks without anything left on the conrods so i guess not. :?

 

[VWAIRCOOLED]

Did you have the flywheel off and change any of the shims for thicker ones to remove end float?

 

[Dean]

Not a single thing on the bottom end was touched. I've got a fair bit of study and cramming to do for a couple of weeks so i won't be able to touch it for a bit. Bloody thing is at the back of mind though!