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4JG2 Bent Pushrod / Head Gasket Rebuild Advice

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Re: 4JG2 Bent Pushrod / Head Gasket Rebuild Advice

Postby geeves » Tue Sep 13, 2016 5:32 am

4jb1 in an automatic wizard would give disappointing performance without a few tweaks. That seller is a member here and could be a good source of 4jg2 bits as well
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: 4JG2 Bent Pushrod / Head Gasket Rebuild Advice

Postby isuzurob » Tue Sep 13, 2016 6:49 pm

Yip thats me, 4jb1 is direct injection with no pre comp chambers, 4jg2 is indirect and has pre comp chambers, head will bolt to block but wont work
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Re: 4JG2 Bent Pushrod / Head Gasket Rebuild Advice

Postby Mudbomber » Tue Sep 13, 2016 6:53 pm

Ah cool bro, I just hit you up on trademe :) Thanks for letting me know. I might just have to sell a bunch of stuff and get a new head package at this point. Do you have 4 pushrods I could grab for cheap?
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Re: 4JG2 Bent Pushrod / Head Gasket Rebuild Advice

Postby isuzurob » Tue Sep 13, 2016 7:17 pm

ok, i may have some 4jb1 pushrods im preety sure they are the same, are any of the cam followers broken? normally its breaks them aswell, do have a head off a 3.1 that was running fine but safer to buy a new one, just spend abit more and buy a decent brand head
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Re: 4JG2 Bent Pushrod / Head Gasket Rebuild Advice

Postby Mudbomber » Tue Sep 13, 2016 7:26 pm

Choice man, yeah I was thinking of getting a set of pushrods from ebay but it'll take a while. I haven't checked the followers, thought they were hydrolic lifters but guess I'll see when I pop them out :) I have 4 bent rods, engine got hot and cam belt skipped some teeth and one set of valves hit the pistons. No marks on them that I can see and valves look good too. I'll pull the followers out tomorrow and inspect, is it fairly obvious if they are broken? I may take those pushrods off you though as it'll be faster, check the auction and tell me what you think?
http://www.ebay.co.uk/itm/271095155161?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

Then buy a new head and gasket set. Match my valves to the head, load springs and I'm away :) ???
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Re: 4JG2 Bent Pushrod / Head Gasket Rebuild Advice

Postby isuzurob » Wed Sep 14, 2016 4:50 pm

its a major to check if they are broken visually, thats sump off front off the motor remove cam and check followers, normally it breaks the mushroom off the end of the bit the push rods sit in, you may be able to shine a torch dwn the holes and see if any are missing
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Re: 4JG2 Bent Pushrod / Head Gasket Rebuild Advice

Postby Mudbomber » Wed Sep 14, 2016 6:30 pm

Cool cool. At the moment rad is out and it's pretty empty in there. I was thinking remove the cam belt, as I'm going to change it, then pull the followers out the top? Or is that not how it works. I thought take them out the top, then remove cam belt and pull the cam out the front and inspect. I don't know though I'm thinking of a chevy V8 as that was the last time I had a vehicle with pushrods lol :) I found a new bare head for $380. I'll use my valves and springs, match them to the valve seats and reload the head replacing the 4 bent pushrods. Then new head gasket and all new gaskets upstairs on the motor. EGR delete. Then do the timing belt correctly with a new one, I'm there and it's only $30 even though it was done 30K ago, set the valves and spin it over by hand to make sure nothing it hitting. New rad and the best coolant I can buy and fresh oil and air filter. Purge the diesel system and then crank it over. Hopefully all goes well. Check out the engine bay pic, heaps of room to pull the cam forward, if that's how it works. No increasing the boost or fueling, it's for the wife and I don't want to stress it. Just make it run a little better and cooler. Might pull the thermostat so it runs cooler like my VW does (yes I know diesels run more efficiently at operating temp).
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Re: 4JG2 Bent Pushrod / Head Gasket Rebuild Advice

Postby isuzurob » Thu Sep 15, 2016 5:47 pm

as i said above have to remove sump and complete front alloy cover to get the cam out, followers come out the bottom through the bottom of the motor, so its motor out job
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Re: 4JG2 Bent Pushrod / Head Gasket Rebuild Advice

Postby Mudbomber » Sun Sep 18, 2016 7:36 pm

Ok... scored an untested engine for real cheap from a wrecker. At worst case I can sell the diesel pump to get my money back and harvest the pushrods, cam and followers if it's no good. Or even the shortblock. It has has some rain go into it though in the past 2 days as the injectors were taken out so I turned it over by hand (which feels good, it's not rusted siezed or anything is just happened) and turned it upside down and turned it over so any water would come out the ports of injector holes. Some came out but no biggie. I'm was thinking of filling the cylinders with diesel tomorrow and then draining them out again similar to the water and using my long reach airgun to make sure their pretty clean. Pain in the butt, but it was cheap and everything is there and it looks pretty good. No way to tell really without installing it I think. As Rob said I need to take my other shortblock out anyways to get to the cam and lifters so I'll gamble 1 day to chuck this one in and see. I'll also use my USB endoscope to peer into the cyliners and make sure they look good, no cracks in the head for instance.

Bit of a gamble but it's just time I reckon. Water is a bummer, but the diesel pump that came with it will see me recoup all my money and then some and I can keep this shortblock or pushrods etc if needed. Has all the sensors and things too so sweet as.

Question is, I have a compression tester but it doesn't fit in the injector holes, they are far too bit. Anyone have any other suggestions? There is zero oil in the water and zero water in the oil. The bighorn I got it from had only minor damage but it's rego was over a year old so I'm hoping it had lapsed and that is why it was there. Slim chance, I bet it also has a cracked head but at least I get the parts I need. It was real cheap but I suppose you get what you pay for... most of the time ;)
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Re: 4JG2 Bent Pushrod / Head Gasket Rebuild Advice

Postby isuzurob » Tue Sep 20, 2016 4:15 pm

As you said was a good find, can do compression test through the glow plug holes
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Re: 4JG2 Bent Pushrod / Head Gasket Rebuild Advice

Postby Mudbomber » Wed Sep 21, 2016 7:05 am

Ah too right! I'll have to find the adapter for my compression guage though. Thanks man I would have over looked that!
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Re: 4JG2 Bent Pushrod / Head Gasket Rebuild Advice

Postby pig75 » Wed Sep 21, 2016 3:44 pm

Make sure it's a diesel comp gauge as petrol ones aren't big enough
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Re: 4JG2 Bent Pushrod / Head Gasket Rebuild Advice

Postby Mudbomber » Wed Sep 21, 2016 6:08 pm

Ah yup. I think mine is just for petrol. I'll try and track one down. I should be able to do it with the engine out and just turning it over by hand eh? I was doing that today after pressure washing it and then putting diesel in the cylinders to line the inside with diesel and it was making a smokey kind of mist out the exhaust manifold. Not firing but it seems to have compression, only a gauge will tell though. Actually, nevermind. When I pull the shortblock out of the vehicle I'll put the starter on it and turn it over to read the compression :)
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Re: 4JG2 Bent Pushrod / Head Gasket Rebuild Advice

Postby geeves » Thu Sep 22, 2016 5:58 am

No it has to be done on the starter with a good battery. It will give a reading that may give an indication of trouble but it will read low and can you wind every piston at the same speed?
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: 4JG2 Bent Pushrod / Head Gasket Rebuild Advice

Postby Mudbomber » Thu Dec 22, 2016 8:00 pm

Ok... new engine I'm taking a chance on installed! That didn't take long lol. EGR delete too. How the heck do I prime the diesel system? I used the lift pump and cranked it for a bit but nothing is coming out the back of the pump. I made sure the solendoid is getting 12V and can hear it click. I tried ising a syringe with the ignition on to push diesel through and nothing. Then losened the last inkector fitting to try and crank and still no dice. Maybe the pump is toast and that is why it was at the wreckers? I do have anothe rpump...
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Re: 4JG2 Bent Pushrod / Head Gasket Rebuild Advice

Postby geeves » Fri Dec 23, 2016 6:16 am

Do you have diesl at the inlet to the pump?
You need to pump till it goes hard
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: 4JG2 Bent Pushrod / Head Gasket Rebuild Advice

Postby Mudbomber » Fri Dec 23, 2016 12:30 pm

Hi Geeves,

Yesw I used the primer till it was stiff. And it does push diesel through to the other side. Which injector line should I crack first?
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Re: 4JG2 Bent Pushrod / Head Gasket Rebuild Advice

Postby Mudbomber » Sat Dec 24, 2016 8:29 am

Awe I think I gambled and lost... :(... I got it started and I have to have my foot on the gas to get it going. Once running it's a dog and knocks and smells like diesel and smokes something fierce. When I take my foot off the gas, it dies. I think there is oil in the coolant but that could be left over from the used radiator I installed. Hmm. Could be anything now. Time to start eliminating before I take the head off. I have a petrol compression tester but it won't fit into the glow plug holes. This engine came from a wreckers for cheap and is probably poked. But... I need to eliminate other stuff first as if it was the diesel pump for instance I have another one of those. Strange I need to start i with the foot on the gas to get it going. Check out the video, let me know what you think, I'll ask around for a diesel compression tester. Have a look at the video and tell me what you think, it smelled real strong of diesel as well.

https://youtu.be/dOiNj41tWh4
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Re: 4JG2 Bent Pushrod / Head Gasket Rebuild Advice

Postby isuzurob » Sun Dec 25, 2016 6:40 am

sounds like it has 1 cylinder with no compression as its chuffing
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Re: 4JG2 Bent Pushrod / Head Gasket Rebuild Advice

Postby geeves » Sun Dec 25, 2016 6:50 am

I dont know. Under cranking all the compression strokes sounded the same.
Start by loosening the pipe to each injector in turn. Remember its under pressure so wear gloves and glasses. That will find the cylinder. Try swaping this and any other injector for starters
Sanding your knuckles before starting work can help. That way you cant skin them
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