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1995 Bighorn 4gj2t Timing Belt Replacement

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1995 Bighorn 4gj2t Timing Belt Replacement

Postby Motang2 » Sun Nov 14, 2021 5:46 pm

Hi everyone,
I am about to give my wagon a front end overhaul at 200,000kms. This includes timing belt, tensioners x2, water pump, main seal plus fuel pump and camshaft seals etc. I have a Pdf Manual for the 4jg2 engine however, it shows the timing is driven by geared wheels and not belt driven like mine. I would appreciate any guidelines or if someone might have a Pdf download for this repair/ replacement? I was told that the belt replacement etc is the same as for the 4jb1 or 4jj1 engines. A garage did the 100,000km belt change, its my turn this time so I would appreciate any help please! Cheers
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Re: 1995 Bighorn 4gj2t Timing Belt Replacement

Postby Motang2 » Sun Nov 21, 2021 11:32 am

I just tried to follow up and I came up with the following ERROR message -

General Error
SQL ERROR [ mysql4 ]

Incorrect string value: '\xF0\x9F\x91\x8D\xF0\x9F...' for column `acupunct_clubisuzu`.`phpbb_posts`.`post_text` at row 1 [1366]

An SQL error occurred while fetching this page. Please contact the Board Administrator if this problem persists.
Please notify the board administrator or webmaster: admin@clubisuzu.com

I have saved the post in Word. Please advise?
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Re: 1995 Bighorn 4gj2t Timing Belt Replacement

Postby geeves » Sun Nov 21, 2021 4:12 pm

Re the sql error they often go away. Ignor it unless it happens again.
Re the belt drive manual. Ive just emailed a copy to the email address you signed up with
alan
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: 1995 Bighorn 4gj2t Timing Belt Replacement

Postby Motang2 » Sun Nov 21, 2021 6:56 pm

Thanks again Alan,
That will be handy for future use. I took the plunge and have successfully completed the above job over the past week. I got help from mechanical friends over the phone and I used Google and U-tube plus common sense and caution. I tried earlier today to send a post on some relevant handy hints and warnings for the Timing Belt and Seal replacement procedures I experienced on my Bighorn 4gj2 but it kept failing to send? Maybe it was too large?? I will continue to try and send it later.
Cheers, Jake
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Re: 1995 Bighorn 4gj2t Timing Belt Replacement

Postby Motang2 » Mon Nov 22, 2021 1:40 am

Decided to take the plunge so went ahead and did job. I got help from mechanical friends (on the phone), common sense and Google (even if some of it I think was shit!). A week later all done and tested, very happy with the job!

I am a self taught handyman and I found the job a little tough not knowing some of the procedures and possible pitfalls, in retrospect I would of preferred a manual or to have even taken it to my local garage to fix but hey, we are in Covid Lockdown and I guess I got the time to do it!

Here are some handy hints, procedures and pitfalls I learnt on this job! Appreciate comments please, you may have some better ideas or tricks etc?
1) I removed the radiator for better access (not all members agreed with this?) I also wanted to remove the AC condenser but thought against it as I didn't want to deal with re-gassing problems!
2) I used a 24mm socket and strong arm against the chassis and a flick on the starter motor to crack the crankshaft pulley bolt.
3) I made a suitable lever from 30 x 6mm MS flat, I drilled two 8mm holes in it, ground the centre and bolted it to the camshaft sprocket in order to crack the sprocket bolt. I thought the 2 o'clock retainer timing bolt was inadequate to hold the sprocket as the bolt was bloody tight! I also did not want to risk the possibility of damage from bottoming out the valves onto the pistons??
4) With a white marker, I marked a tooth position of the crankshaft gear, the camshaft sprocket, and the injector pump sprocket on both the gears and on the old timing belt before disassembly. This is a great for re-assembly, you can transfer the marks to your new belt and providing you have your 3 sprockets at TDC on No1, all marks should line up!
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Re: 1995 Bighorn 4gj2t Timing Belt Replacement

Postby Motang2 » Mon Nov 22, 2021 2:09 am

NB:- This is a continuation of the above post!
5) In NZ there are options and differences in buying Timing Belt Kits. I was able to identify my belt as having 119 square teeth and was able to shop online for the best price!
6) I used a small gear puller to remove the Crankshaft Pulley and the Camshaft Sprocket hubs.
7) I drilled a small hole in the crankshaft seal and used a self tapping screw to remove it. I jimmied the speedy sleeve off the crankshaft with a small-soft screwdriver and hammer. NO damage to crankshaft or housing! The camshaft seal was a piece of cake.
8) I installed the new crankshaft seal by screwing it in using the gear and hub. The camshaft was similar and I used large sockets and a hammer for final position.
9) I tightened and torqued the cam sprocket in reverse to disassembly.
10) Once the all the sprockets, the timing belt and the new idler pulley were in their correct positions, it seemed best to install the tensioner pulley last and leave the holding bolt loose. I found out on U-Tube that the funny looking lever next to the tensioner is required. The locking bolt is removed and the fulcrum bolt loosened. Check that all your marks line up ( No1 should be at TDC). Using a spring balance exert 9kg at the outermost hole on the lever then tighten the tensioner pulley bolt.
11) I torqued the crankshaft pulley bolt to 206Nm with the manual gearbox in 5th gear and handbrake on - I hope this was not too hard on the drive train??

I gave it a hard test run over 30km and all the guages were positive, it never missed a beat and there were no leaks showing the next morning. I am happy!
Last edited by Motang2 on Mon Nov 22, 2021 7:34 pm, edited 3 times in total.
Motang2
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Re: 1995 Bighorn 4gj2t Timing Belt Replacement

Postby geeves » Mon Nov 22, 2021 3:41 pm

Big word of warning on your method. You are not meant to undo that 24mm bolt except to access the seal. The pulley has 4 smaller bolts which allow the pully to come off to remove the timing cover. Make doubilly sure that bolt is torqued correctly or it will come loose. If it comes loose it can damage the crankshaft.
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: 1995 Bighorn 4gj2t Timing Belt Replacement

Postby Motang2 » Mon Nov 22, 2021 7:49 pm

Thanks for that Alan, I think you might of missed the second part of my post where I did mention that I replaced the front crankshaft seal.

I had a hell of a job sending my follow-up post due to that "error problem" so I sent it in two halves. I found that the "error" was due to the Smilie Face I had on the second part. Once deleted it flew through!
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Re: 1995 Bighorn 4gj2t Timing Belt Replacement

Postby geeves » Tue Nov 23, 2021 7:03 am

ok point 11 seen. When I purchased my first Isuzu I had the belt changed as part of the sale by an unknown mechanic. 5 years later a knocking noise in the engine and a mechanic said check the crank bolt as the pulley is wobbling. I put my hand in there and said "what bolt?" All that was holding the timing pulley on was the tension of the fan belt. I got lucky that day
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: 1995 Bighorn 4gj2t Timing Belt Replacement

Postby Motang2 » Tue Nov 23, 2021 11:25 am

Many thanks, I will keep my 24mm socket handy over the next few months! Cheers
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