Land Cruiser FJ 45 engine ? noise

Submitted: Wednesday, Mar 05, 2008 at 21:05

ThreadID: 55220 Views:3358 Replies:7 FollowUps:2

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offroader

Greetings from sunny South africa.
I have an FJ45 Cruiser that has a noise that I can't identify. When you run the engine at any rev, no noise. As soon as you put the vehicle into gear and start to pull off, a heart knocking noise is heard. Sound something like a big end knock??? While driving the knock can be heard but not too loudly. When putting on the power, as in uphill, the noise increases. Everyone I've spoken to here has a different opinion! Any ideas? I'd like some help before I start pulling things apart.

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Reply By: Tony - Wednesday, Mar 05, 2008 at 21:26

Wednesday, Mar 05, 2008 at 21:26

Are you sure it's coming from the engine?

Other possibilites could be, uni joints in drive shaft, diff bearings, broken CV (unlikely), or wheel bearings.

If engine, yep big end bearing or broken con rod.

AnswerID: 291002

Reply By: offroader - Wednesday, Mar 05, 2008 at 21:44

Wednesday, Mar 05, 2008 at 21:44

Thanks for your reply Tony.
It is hard to say where it is coming from. It sounds like it is coming from the engine but when you rev it out of gear there is no hint of a noise, no matter how hard you rev it. I don't think it is any uni joint etc because once in gear the noise is heard as soon as you start to pull off, before you are even really moving. As soon as you start letting the clutch out, putting the engine under load, the noise is there. ????????

AnswerID: 291015

Follow Up By: splits - Wednesday, Mar 05, 2008 at 21:47

Wednesday, Mar 05, 2008 at 21:47

You could try isolating each cylinder by driving while disconnecting the plug leads one at a time. The engine will misfire but you will also ease the load on the piston and bearings in that cylinder. If the noise stops or changes then the problem is most likely something serious like bearings.

I would also check the oil pressure. Worn bearings will cause low pressure but the bearings may have worn out in the first place because the oil pump is not putting out enough pressure so check both.

Brian

FollowupID: 556432

Reply By: Tony - Wednesday, Mar 05, 2008 at 22:00

Wednesday, Mar 05, 2008 at 22:00

Ok to eliminate front/rear noises to the drive train, means you will have to remove rear tail shaft and drive on the front axle. Put it back, and do the same for the front.

Or jack up each end and spil by hand, listening for bearing noises.

For engine, out of gear, pull out plugs and turn engine over on crank handle.

A lot of stuffing around, but.

AnswerID: 291030

Follow Up By: Tony - Wednesday, Mar 05, 2008 at 22:01

Wednesday, Mar 05, 2008 at 22:01

"spin by hand" not spil by hand.

FollowupID: 556441

Reply By: pop2jocem - Wednesday, Mar 05, 2008 at 22:24

Wednesday, Mar 05, 2008 at 22:24

Hi Offroader

I once had a customer that had a knocking noise that was only there when he drove off. He had a fairly early model FJ 45 (this was a lot of years ago). It turned out to be a broken tooth on a gear in the gearbox.

Cheers Pop

AnswerID: 291043

Reply By: Mikee5 (Logan QLD) - Thursday, Mar 06, 2008 at 10:36

Thursday, Mar 06, 2008 at 10:36

Back in 1978, on my 1976 FJ40, the dog clutch selector for changing from H2 to H4 broke a piece off. It got mobile within the transfer case and then broke a tooth of the high range gear. All I heard was a knock when driving. Had to strip down and rebuild T/case. Check your oils for scraps of metal on the magnetic plugs in gearbox, t/case and diffs. That may help finding any damage. Good luck. Did Toyota help with the cost of repairs on a 2 year old truck - no way!!!!

AnswerID: 291109

Reply By: Member - Shane D (QLD) - Thursday, Mar 06, 2008 at 21:58

Thursday, Mar 06, 2008 at 21:58

Try and "load" up the motor buy putting in gear, hand brake ON and letting out the clutch, this way the gearbox/driveline is not moving, if noise appears, I'd say Bigend or mains.
When you put your foot on the clutch you actually put forward pressure on the crankshaft, causing it to "float" out of position, By loading up motor and not moving the driveline, you can go about the elimination process, whether g/box or motor

Shane

AnswerID: 291269