1hz timing belt, motor won’t turn by hand

Submitted: Saturday, Sep 12, 2020 at 21:59
ThreadID: 140503 Views:12139 Replies:5 FollowUps:12
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I have changed the water pump and timing belt and put the belt on. turned motor over with the original stretched tension spring in pIace while was waiting for the replacement spring. Now the motor when turned by hand is getting stuck/ locking up while hand turning of the crank. Have I put it out some how? If so how do I return the cam and fuel pump sprockets to tdc or bdc without breaking it please help?
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Reply By: Blown4by - Sunday, Sep 13, 2020 at 06:38

Sunday, Sep 13, 2020 at 06:38
Mate it sounds like the pistons are hitting the valves because the valve timing is out. You need to slacken the belt tensioner, remove the belt & get all the valve timing marks on all the cam belt pulleys crankshaft, etc in their correct positions. The pulley marks usually consist of what looks like a big centre punch mark on the front face of each pulley on the flat face next to the pulley teeth. Those marks in turn line up with other markers on the fixed part of of the engine like an arrow or similar. When you have the marks all in their correct static positions, have a look at the belt OD & there should be some straight white lines going across the flat face of the belt. These are your belt timing marks which in turn line up with the pulley timing marks when the belt is fitted in its correct position. Fit the belt, let the belt tensioner do its thing, then turn the engine by hand two full turns, firstly to tension the belt & secondly to make sure you don't have the problem you have now. On no account start the engine like it now or you will in l liklehood finish up with bent valves & damaged pistons & a whole world of pain that you are trying to avoid by correctly doing your preventative maintenance before the belt breaks.
TIP: NEVER attempt to turn the camshafts by the bolt head that holds the belt pulley on to the camshafts.
AnswerID: 633383

Follow Up By: Nicholas L - Sunday, Sep 13, 2020 at 07:40

Sunday, Sep 13, 2020 at 07:40
Legend thanks for you advice just didn’t want to bend anything due to ignorance. Will the cam have to turn in some sort of order with the pistons/ rest of the motors timing?
FollowupID: 910414

Follow Up By: RMD - Sunday, Sep 13, 2020 at 08:30

Sunday, Sep 13, 2020 at 08:30
Respect all of the above and try to remember which way the engine and cam have been turned, BECAUSE, to enable realignment of the above items mentioned you may have to turn the engine slightly and the cam one after the other in the opposite direction, to enable return to original timing mark align!ENT position. First up I would disconnect the battery so NO MISTAKE IS MADE WITH STARTER.
FollowupID: 910415

Follow Up By: Nicholas L - Sunday, Sep 13, 2020 at 09:12

Sunday, Sep 13, 2020 at 09:12
I will do and should be apparent from timing marks how far it is out roughly when I pull the belt off
FollowupID: 910416

Follow Up By: qldcamper - Sunday, Sep 13, 2020 at 09:15

Sunday, Sep 13, 2020 at 09:15
Will be tricky to do if you didnt set the engine to TDC before removing the belt.

Try to measure the position of the crank pulley away from TDC in degrees then set the cam accordingly half as many degrees from its marks.

Hopfully this will get you close enough for the engine to be turned by hand to TDC compression to lign up the marks correctly.

Will repeat what RMD said,
Disconnect the battery.
Then the engine GENTLY by hand.
FollowupID: 910417

Follow Up By: HKB Electronics - Sunday, Sep 13, 2020 at 09:32

Sunday, Sep 13, 2020 at 09:32
First, if you have cranked the motor using the starter you have most likely bent a valve.

If it is a standard setup same as most other motors it will have timing marks on the crank shaft, cam shafts and anything else that needs it, just align the timing marks and install the belt. May need to install crankshaft pulley if the crankshaft gear is not marked. If your very unlucky you may need a tool.

If you don't know where the timing marks are you most likely don't have a workshop manual, I would suggest you buy one as it will give detailed instructions and list the correct torques for bolts etc.

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FollowupID: 910418

Follow Up By: RMD - Sunday, Sep 13, 2020 at 09:59

Sunday, Sep 13, 2020 at 09:59
QLD camper is spot on with precautions regarding engine / cam relationship and the turning of everything.
IF THE ENGINE WASN'T SET AT TCD at the outset , then the crank and cam will have to be sequentially turned incrementally so collision is being avoided. Until ALL can be finally aligned so the timing can be set. Some understanding of engine firing order will be of assistance..
FollowupID: 910419

Reply By: tonysmc - Sunday, Sep 13, 2020 at 10:06

Sunday, Sep 13, 2020 at 10:06
Hand crank it back to where you started and check the alignment again. Here's the manual if it helps,
Remember that just because the marks line up you may not have No 1 cylinder at top dead centre, you may be one full turn out!
AnswerID: 633388

Follow Up By: RMD - Sunday, Sep 13, 2020 at 13:36

Sunday, Sep 13, 2020 at 13:36
Unlikely to get to one full turn out since the pistons and valve will Kiss each other long before that. degrees so you cannot pass that or even get near it or valves and pistons WILL touch with component destroying force, hence the careful slow, no forced rotation above. There is a firing stroke each120 degrees. Cannot turn one with out turning the other, otherwise crashing will happen. If it IS one turn out his engine is knackered.
FollowupID: 910423

Follow Up By: tonysmc - Sunday, Sep 13, 2020 at 14:34

Sunday, Sep 13, 2020 at 14:34
What I was saying is that he may have started one full turn out and to only hand crank it back in the opposite direction to where he started hand cranking it. Obviously if it is out of alignment he wouldn't be able to rotate it a full turn. If he is only hand turning the motor it will hardly be knackered!
What some people do is cut the original belt in half longways and the half slide the new belt on and then cut the old one off and side the new one the rest of the way! Too late for that now.
FollowupID: 910426

Follow Up By: RMD - Sunday, Sep 13, 2020 at 23:10

Sunday, Sep 13, 2020 at 23:10
If he did begin, one turn out, No 6 would be near TDC but the cam would be 1/2 turn out in it's marks so can it be that way? The cam marks cannot line up! Pump marks will also be around 1/2 turn off too.
FollowupID: 910433

Reply By: qldcamper - Sunday, Sep 13, 2020 at 11:11

Sunday, Sep 13, 2020 at 11:11
Did you crank the engine with the starter with the old spring? If you have previously answered this I must have missed it.

If you had everything lined up ok the spring would have made no difference, it was working well enough before you did the job it should still have enough tension to do a test turn although the starter isnt a wise way to do it.

If the valve timing was far out you should have noticed a very different noise while cranking.

If you have never turned a diesel by hand they are bloody hard to get through compression compared to a petrol engine.

If it is your lucky day this might be all it is.
AnswerID: 633391

Reply By: Member - DOZER - Sunday, Sep 13, 2020 at 13:33

Sunday, Sep 13, 2020 at 13:33
These motors are interference motors, the front crank pulley marks are not top dead centre but bottom dead centre, this is so all the other marks line up and the belt can be changed/safe to move the cam away from piston contact with valves. If you have used the starter, start planning to take the head off. If you havnt, loosen all the bolts that hold the cam to the head, do it evenly. This will close the open valves and allow you to turn the motor back to line the timing marks on the crank harmonic balancer. If it is on no1 bdc, the marks on the timing belt cogs will be in the correct place. If not, turn 180 degrees and check again. Do up cam, check key is not sheared in belt pulley and try again.
AnswerID: 633393

Follow Up By: RMD - Sunday, Sep 13, 2020 at 13:45

Sunday, Sep 13, 2020 at 13:45
The manual shows timing pulley alignment with the engine case and indicates the valve buckets on No 1 cylinder should be loose and No6 buckets tight. That is a sure sign of TDC and not BTD positioning.
If his cam buckets are as mentioned and the crank pulley is near to the mark and it hasn't had a full crank turn then it has to be near TDC on No1.
The only time you can rotate the crank one full turn is if there is NO head, or No valves or there is no cams in the head. As said "interference motor".
FollowupID: 910425

Follow Up By: Member - DOZER - Tuesday, Sep 15, 2020 at 07:12

Tuesday, Sep 15, 2020 at 07:12
Its been a while since i rebuilt my hdft, maybe i am getting confused with aligning the timing gears, or setting the pump up, but i do recall aligning bottom dead centre at some stage. In the scenario you mention, no1 is on tdc and no 6 is rocking between exhaust and inlet. The best thing to do in this scenario we are replying to is turn the motor backwards, keeping the cam belt tight on the leading edge till it returns to installation position.
FollowupID: 910450

Follow Up By: RMD - Tuesday, Sep 15, 2020 at 08:23

Tuesday, Sep 15, 2020 at 08:23
Unfortunately, on these motors, there are no rocker arms to rock, so only cam bucket clearance/looseness/freeness, to be detected for being close to TDC on No1 and No 6.
FollowupID: 910453

Reply By: qldcamper - Monday, Sep 28, 2020 at 10:58

Monday, Sep 28, 2020 at 10:58
Any updates?
AnswerID: 633562

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