Engine turns then jams

[fosley]

My question about the bearings: how exactly did you check the bearings? Did you check the clearances and roundness, etc., or did you just wiggle them to check for slop? When checking for rod knock, you check for slop (if there wasn't slop, it wouldn't be slapping), but if the bearing is seizing the motor, that means there's less than zero clearance at certain points, and could be normal-ish clearances around the rest (I almost guarantee you won't be able to feel a .01 inch clearance difference by hand, and less difference can seize the motor).

[reights]

By checking the bearings I removed the caps (connecting first and then main) one by one and try turning the engine. Same exact problem. I removed the gear box which includes removal of the starter and had the same problem.

The problem only started after the car was parked for about 2 weeks. The car ran fine before then. The engine was not knocking or not missing before hand.

The main question I have though what can possibly cause the problem if the car was parked beforehand

[Weasy2k]

nothing! I dont see what could happen....thats the stumper

[fosley]

Well, I wouldn't think a mere 2 weeks would hurt, but over time the oil will drain out and it could just possibly cause problems. Seems unlikely, but that's my first guess.

When you were checking them one at a time, did you pull all the rods without reconnecting the first one? If not, it's possible you messed up two or more bearings, but given the unlikeliness of one, that's stretching it.

Hmmm. If it's not the bearings, the tranny, the starter/flywheel, the pistons or hydrolock. . . well, not likely, but it could be the A/C or alternator (you can check them by loosening the belts until they would just slip) or the oil or water pump. The pumps are on the timing belt, so that makes it a pain, but you might pull the timing belt to see if the cams are seizing anyways. I've seen cams seize once, but that was after about a minute of having zero oil pressure, so even that seems unlikely.

I think this is highly unlikely, but are you sure that nothing is hitting internally? A snap ring could break, letting the wristpin slide out and preventing the piston from sliding all the way up. Something could have somehow (?) gotten stuck on the crank and now it's hitting the block. Not sure how, but it's an idea that's easy enough to check if the oilpan is already off.

[reights]

I pulled the head and the engine started to spin. There is alot of carbon build up on the pistons. That might be the problem i'm having still don't understand why it would jam after sitting for some time.
Seeing that i have the head off, i'm thinking on new rings and bearings. anybody knows where i can get a rebuild kit for a reasonable prize?

[mrturrari]

Carbon buildup would have to be more then 1mm thick to cause the engine to stop and then it would still go almost all the way around not just 180 degrees. If you set the head back on and turn the crank around does the head lift? Also the deck height should be close to zero so if you turn the engine and any of your pistons rise more then a few of thousanths above the block you have a problem on the bottom end.

If you found nothing in the cylinders and nothing is protruding from the head then chances are you spun a bearing, either one of the rods or one of the mains. It could have had too much oil clearance from a previous oil starvation or a few forgotten oil changes and then with 2 weeks of sitting there all the oil drained out and it spun when you tried to start it.

As was said before whatever the problem is, it would be a good idea to get the block on an engine stand so you can take it completely apart and check all the clearances. If you plan to do bearings and rings anyway this will make that much easier too.

[Weasy2k]

^ do what he says

[reights]

The carbon build up is alot more then 1mm. The engine jams when the pistons (number 4 +3 cylinder) with most build up is almost tdc (top dead center).

I will be pulling the engine and rebuilding now, no question there.

[fosley]

Well, that sucks, but glad you found the problem. I can't remember what brand it was, but I got my rebuild kit through a machine shop. You can get one from this site for $287. (I just did a Google search, so I don't know if they're reliable.) I would suggest doing the oil and water pumps while you're there, just because it's they're a pain to get to later and this way you'll know they're good.

The reason it would only spin 180° is because the 2 and 3 pistons are 180° off from the 1 and 4 pistons. It will spin clockwise until the 1 and 4 pistons are at almost TDC, then counter until the 2 and 3 pistons are at almost TDC (or vice versa, depending on which way it got stuck).

[reights]

The engine is back together and spins perfectly after part delay from toyota dealer. Put the engine in on Tuesday did not have time to connect up all of the wires will be working on that over the weekend. hopefully will be back on the road again by late Saturday. Any tips on break in procedures for a rebuild engine?

[fosley]

Do you have your manual? It should have the break-in procedures. Normally, I think you're just supposed to keep it under like 60 mph and 4K RPM for about 500 miles. Also, vary your speed/RPM so it beds in across the whole range. After the break-in, change the oil to get rid of the metal shavings that are part of the bedding process.

Some people suggest that you drive it like you stole it as soon as the oil has a chance to lube everything up. Iunno about that one though.

Also, don't use synthetic for break-in. It's so slick it can actually prevent the rings from bedding properly (so I hear).

Edit: And congrats on getting the motor back together!

[Gairloch]

Here's a link that explains the thinking behind the hard break in method.

Break In Secrets--How To Break In New Motorcycle and Car Engines For More Power

[mrturrari]

Good deal. I follow the more aggressive break-in school of thought. Break it in like you are going to drive it... well almost. This is only if you replaced the rings. First make sure everything is working as it should and don't idle it for too long. Especially look for oil leaks. Once it is warmed up take it out and do some good full throttle pulls in different gears followed by engine braking trying to cover as much of the RPMs as you can without going over about 5000rpms. Do that at least a couple of dozen times and then city drive it for the first 20 miles. Keep doing the accelerate and decelerate thing as much as you can but if your are in traffic it's difficult. Just try to vary a lot and shift gears to make sure you are covering different RPM ranges. After 20 miles change the oil and then for the next 1000 miles change the oil a couple of more times. For the next 500-1000 miles don't exceed about 5000rpms and try not to stay at the same RPM all the time.

The only real reason not to use synthetic is that it costs more so for the first while just use the cheap stuff.

[reights]

Engine back in but i have a few probs

1. Overheating (i know its a pain to purge the system properly).
2. After the car gets up to operation temp. if i rough up the car looks like it looses power i.e. the lights in the dash comes on and the car start to jerk. just wondering if anybody knows what could be causing that problem?
3. Clutch switch stop working. I have to push the switch with my hand in order to start. does not work when i press the clutch to the floor.

[fosley]

1. Could be a lot of things, like not being bled completely. Do you get white smoke/steam out the exhaust?

2. Bad ground? Are you sure all your ground wires are attached properly and are clean? Or maybe an alternator connector.

3. There should be a little plastic piece attached to the clutch pedal that pushes the switch. If this piece breaks off, the switch goes through the hole in the pedal and doesn't trip. My CRX brake switch did this about a week ago and a new peice was about $3 from Honda; I'd guess a similar price from Toyota if that's your problem. Since the switch works, I'd guess that's your problem. Alternately, the tab the plastic stopper is attached to could have bent or broken. Either way, I'm thinking coincidental timing, since the switch itself still works (and therefore everything related to pulling the motor/trans.

Edit: the part number for the plastic piece (called a "cushion, no.3, for clutch pedal") is 90541-06036 and according to partznet the list price is $0.89, or you can buy it from them for $0.68.

[reights]

1. Well the overheating is fixed part of the problem was the wire for the temp sensor had a cut in it and was touching on the transmission

2. Was actually both went over all my connectors today and found that i forgot to tighten the alternator and ground wire that goes on the intake.

3. Fixed. The lil rubber fell out as you say found it on the floor of the car.

Thank you for your help...

[f300]

just an idea for your running in, and the presence of metal shavings in your oil - I always attach a magnet from a computer hard drive onto the oil filter. It should pick up the metal in the oil system...

[Gairloch]

You just stick it to the outside of the filter? Do you tape it on there or what?