Problems firing rebuilt L6

[realrain]

Ok, i'll start with everything ive done.

Honed and rehashed cylinders, new rings, one new piston, new rod bearings on #5 and #6 (i got the engine dissassembled and they where missing), and complete reseal.

Im trying to fire this thing off sitting on the floor in my shop and im having to wire two batteries in series to even get it to turn over and it will only crank over fast for 3-4 seconds and slow to a stop. its impossable to turn by hand, ive been using a 3/4" drive rachet which does it pretty easy but not fast enought to get it to pop.

Maybe Too close of a bearing tolerance?

Ive got a 200 amp jump starter but so far all ive used it for is to fast charge the batteries.

On the question of what then engine actually is, i think its a 240cid. The head is off a Plymouth and the block casting # starts P24(star)*****.

Also, what should i get for a ballast for the coil, the fist one i had boiled over and its been along time since i mest with anything that needed one, shouldnt i be able to order one for a 66 chev p.u and is it? (cheap and readily available)

thanks

[BobT-47P15]

I think P24 is a 1954 Plymouth. 230.

[dezeldoc]

Their is a multitude of things that could be wrong. did you put it together with oil or assembly lube? did you check the bearing clearance? are the pistons facing the right way? valves adjusted? see where I am going. you should be able to turn it over with a 1/2" breaker bar. is it 6v or 12v? if it is 6v you don't need a ballast. if 12v any ballast that drops the voltage to around 8v will work.prim the carb and try it that way, but make sure the timing is right first and it should fire, hold on to it as it will dance all over the floor!! good luck.

[realrain]

i got all my parts from a heavy equipment dealer in anchorage, everything was on the shelf, i ordered it for a 218 and everything fit great.

[realrain]

all the pistons are right, used lots of assembley lube, the valves are perfect(spend most of my days doing valve adjustments on Cats), but the bearings i just dropped in, didnt figure i needed to gauge them, i was thinking about it when i put them in and the turning resistance on the crank didnt really change at all when i did the final torque on the rods.

[realrain]

its a 12 volt setup

[realrain]

i dont think i ever saw the oil pressure gauge move when i was cranking it.

[realrain]

Mom was right..... i should have been a Vet.

[rolliejoe]

turn it over again by hand to feel if anything is binding, beyond that everything that was said before.

[Don Coatney]

Before you go any further drop the oil pan and check all bearing clearances (rods and mains) with plastigage. Did you check and set the ring gap for each piston ring (are the new pistons and rings the correct bore size) prior to installing them on the piston. Did you install the piston rods with the squirt hole pointed towards the cam shaft? Did you make sure all piston and main rod caps were installed on the correct location? They are all numbered but you need to look closley for the numbers. Are the new rod bearings you installed the correct size?

When I rebuilt my engine I spun it with the starter on the bench to do a compression check and my engine built oil pressure with the starter motor spinning it over. I also built a live test bench and ran my engine for about 10 hours on the shop floor prior to installing it in my car.

[dezeldoc]

Another dumb thing, did you get the rod and main caps facing tang to tang? putting a rod cap or main on wrong will give ya a problem also. i know about the Cat thing that is what I have done for the past 10yrs. till they retired me!

[realrain]

Don, doc, thanks, i'll get back into the bottom end.

Everything was std size, but i did neglect plastigauging any of the new bearings. I'll loosen the caps up on 5 and 6 and see if it makes a difference, if it does i'll go get some plastigauge and see what i can do.

thanks again.

[rolliejoe]

the first time I used plastigage it probably saved the motor. I had a crank turned among other things and the tolerances were too tight. Some journals

were actually tapered.

[GeorgeLeonard]

In the book "Truck" (which is a great read for people who are into old Mopars), the author rebuilds his flattie from the ground up and afterward installs it into his truck, puts the transmission in high gear, and has someone tow him around for awhile with another truck to loosen things up, wear them in, build oil pressure, etc. before trying to start it. That sounds like a good thing to me, but only if you are certain that everything has been assembled correctly in the first place.

[Don Coatney]

In the book "Truck" (which is a great read for people who are into old Mopars), the author rebuilds his flattie from the ground up and afterward installs it into his truck, puts the transmission in high gear, and has someone tow him around for awhile with another truck to loosen things up, wear them in, build oil pressure, etc. before trying to start it. That sounds like a good thing to me, but only if you are certain that everything has been assembled correctly in the first place.

In my mind that sounds pretty stupid.

[dezeldoc]

Don picture this; the guy is towing it around and all of a sudden the ingition lights off!

[Plymouthy Adams]

I would question the break-in of any cam exposed to this type of handling..

[realrain]

that is interesting.

[BobT-47P15]

Sounds like they were starting the rebuilt engine just like trying to start

an old engine - by pulling the veh and letting out the clutch.

Guess that may do the trick......but might mess up anything that's not

quite right with the rebuild.

[GeorgeLeonard]

In my mind that sounds pretty stupid.

Please dont hold back. Tell me what you really think.