It's been a while since I posted here, but I need some advice. I'm pretty sure my oil pump went out on my '91 Trooper 4 cyl. At 75 miles per hour. 100 miles from home. Today.

I had a new head put in last year and was hoping to get many more years out of it but the motor now sounds like a bag of hammers are attached to the camshaft and one large one attached to the crank.

There's also been a heavy single *clunk* from the right front wheel lately when pulling out of the driveway while turning. Other than that, the body's in good shape, the factory radio works, and there's decent rubber on it. And only 156k on the odo.


So, what do you guys think? Should I call the time of death? Should I get a tarp for my riding mower and move it into the garage for a teardown to check damage? Is it worth it to rebuild? Or, most likely, pay somebody for a rebuild?

If the oil light came on, and you shut it down right away. The engine could still be good. If it ran low on oil and starved and seized or started knocking <img src="/forums/images/graemlins/frown.gif" alt="" /> bad news. Tear it down and look.

I'd look for a good used running motor vs a rebuild, usually cheaper, even in the long run. Unless you find a very good engine builder.

The clunk in the front is likely upper control arm bushings.

Thanks, maxwell417. I'll look at the bushings when the motor runs again.

Turns out that the key may have slipped out of the camshaft gear which loosened up a bit, causing really bad timing. My shop says the top end will need a new cam shaft, gear, and the little parts in between, but the valves aren't bent.

The shop said it's $400 just for a new shaft from Isuzu, but told me if I find a better source for the parts he'll use it. Also needs the timing gear and key, etc. which can be got used somewhere. Off to the Wire search engine unless one of you guys has a source off the tip of their tongue.

If you need a new cam, I'd suggest getting a delta cam from Matt at Independent4x. Lots cheaper than $400. <img src="/forums/images/graemlins/zombie.gif" alt="" /> As for the cam gear, you could probably get that from a junkyard for quite a bit cheaper than Isuzu. At least if they'll let you take it without the whole engine. Some places are like that, some aren't.

Richard <img src="/forums/images/graemlins/patriot.gif" alt="" />

Check your motor mounts closely

Thanks, Socalboke, I'll check those mounts too. I was looking at new cams but the guy at Cylinder Heads International said he'd sell me one for $35. It was an offer I couldn't refuse.

I found the cam gear and the cap that goes behind it at http://www.allhyundaiisuzuparts.com/

They seem to really break down their old Isuzus since no other junkyard I called (coast to coast) had a cam gear laying around and he had a box of them.

clunk could also be the cv shaft banging around, if the C-clip has come off the end!