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I guess I would be actuate to assume this whole process is required to just replace the dist cap and rotor.
Yes it is. I have my 95 to the point of trying to remove the balancer. I'm going to have to find something I can use to break the balancer free. We beat on to for a couple of hours last night, so far nothing and we have soaked it with PB blaster. It is a PITA, could not find a puller that would fit in the tight area around and in front of the balancer.
Anyone actually tried the loosened bolts and start it thing?
Yes it is. I have my 95 to the point of trying to remove the balancer. I'm going to have to find something I can use to break the balancer free. We beat on to for a couple of hours last night, so far nothing and we have soaked it with PB blaster. It is a PITA, could not find a puller that would fit in the tight area around and in front of the balancer.
Anyone actually tried the loosened bolts and start it thing?
Mine was a real mother to get off. I have a lift so It was nice to be under it bit it still took awhile. Make sure you use a big hammer. The extra weight will help. Remember to smear the mounting surfaces in antisieze when you put it back on.
Mine was a real mother to get off. I have a lift so It was nice to be under it bit it still took awhile. Make sure you use a big hammer. The extra weight will help. Remember to smear the mounting surfaces in antisieze when you put it back on.
I think I do need a bigger hammer and a different pry bar to use with it. I need to go pick up another pry bar. Wish me luck!
This falls into the category of "could easily go either way." If you're not reluctant to do the required wrenching, consider replacing the water pump, adding the drain hose to the weep hole, and replacing the rotor and cap on your OEM Opti. You have the second-generation, improved, actively-vented Opti. If the guts of the thing look good, and it's still working well, and its bearings seem to still be good, I think I'd be inclined to re-use the unit with a fresh rotor and cap (be sure to apply Loctite to the rotor-mounting screws), given how problematic it seems to have become for us to get reliable replacement Opti units these days.
Live well,
SJW
Well, it went the wrong way.
I misdiagnosed the leak! It was the friggin weep hole, not the hose. How did I find out? I wanted to get mine out of the garage post haste in order to start on the wife's '95. Bad move. So I drained and flushed, pulled both knock sensors, replaced "bad" hose and refilled.
What I thought was clearly a hose leak was a concentration of spray from the water pump hitting the belt.
So after a 14 mile drive, my '96 Opti is thoroughly soaked in fresh 50/50 dexcool. No symptoms of failure. Yet. But once soaked, is that a foregone conclusion? Everything I read leads me to that.
I misdiagnosed the leak! It was the friggin weep hole, not the hose. How did I find out? I wanted to get mine out of the garage post haste in order to start on the wife's '95. Bad move. So I drained and flushed, pulled both knock sensors, replaced "bad" hose and refilled.
What I thought was clearly a hose leak was a concentration of spray from the water pump hitting the belt.
So after a 14 mile drive, my '96 Opti is thoroughly soaked in fresh 50/50 dexcool. No symptoms of failure. Yet. But once soaked, is that a foregone conclusion? Everything I read leads me to that.
I guess it's time to order the Petris?
I would hold off on that. Suggest you let it run in the driveway for a while, shut it off, let it cool, and see if/how it'll run after a re-start. If it seems okay, maybe drive it around the neighborhood a few times. If all still seems okay, the only remaining risk might be if there was water/coolant intrusion to the bearing, which could lead to bearing failure in the short-term. And only time and use will tell about that, short of removal and inspection.
Against my better judgement, I didn't do a test drive. I fired it up and it ran in the driveway while I looked for leaks. Nada.
Next day, 7 miles to work. Bad smell in parking garage=Coolant. That's when I found the real leak. Sprayed underside of hood a bit, lots of pooling in front of engine.
Both to and from work she ran like a champ. No stumbling, no hesitation. Perfect starts.
Corvette Central has the cap and rotor for $50. I might just go back with your original suggestion, SJW. I'll toss in plugs & wires too.
I misdiagnosed the leak! It was the friggin weep hole, not the hose. How did I find out? I wanted to get mine out of the garage post haste in order to start on the wife's '95. Bad move. So I drained and flushed, pulled both knock sensors, replaced "bad" hose and refilled.
What I thought was clearly a hose leak was a concentration of spray from the water pump hitting the belt.
So after a 14 mile drive, my '96 Opti is thoroughly soaked in fresh 50/50 dexcool. No symptoms of failure. Yet. But once soaked, is that a foregone conclusion? Everything I read leads me to that.
I guess it's time to order the Petris?
This same exact thing happened to my 96 GS. The car seemed to run fine during the optispark bath the water pump gave it at 42,000 miles. So I figured I would leave the optispark alone and change out the water pump and replace the spark plug wires while I was in there.
Well after replacing the water pump and wires now I have a misfire/knock under load (6th gear while accelerating) I did a data log and it shows misfire on cylinder 5.
Car runs great except when I bog it down then it knocks heavily.
I examined the new MSD wires and they don't show any signs of arcing, the number 5 spark plug looks fine.
I should have removed the optispark, then examin it and at least replace the cap and rotor while I had it all apart.
42K is a pretty short run for any part. I guess sitting is as hard on them as running.
Yea with no local source for the cap and rotor, I'm on hold waiting for Corvette Central to ship. She's on jacks in the garage now, drained the dexcool and bottled it. Can't believe how much junk I vacuumed out of the radiator.
Meanwhile, I need to source a hose fitting, hose and tap for the weep hole on the new Gates pump for the next time. Feels like closing the barn door after the horse is long gone.
I'm looking forward to discovering more about this mysterious, infamous scourge of the LT-1.
This saddens me. Does anybody know what was used for triggering, etc?
They used a multi tooth wheel and a magnetic pick up. Their ignition system shares nothing w/ours. Keep in mind; Indmar used their own proprietary ECM, so they didn't need to use any GM systems. They could use any ignition they wanted to. Also, Timing control isn't as critical in a boat as operating temps are much lower, with an abundance of cold water. You could convert any LT1 over to the Indmar hardware, and people have done it. Hard to get parts though.
If you want to get into it, Indmar part number 536050
42K is a pretty short run for any part. I guess sitting is as hard on them as running.
Yea with no local source for the cap and rotor, I'm on hold waiting for Corvette Central to ship. She's on jacks in the garage now, drained the dexcool and bottled it. Can't believe how much junk I vacuumed out of the radiator.
Meanwhile, I need to source a hose fitting, hose and tap for the weep hole on the new Gates pump for the next time. Feels like closing the barn door after the horse is long gone.
I'm looking forward to discovering more about this mysterious, infamous scourge of the LT-1.
I actually got a cap and rotor kit from Rockauto, it was OEM GM and the box had USA on it!
It is all apart in my garage (second go around) I just need to remove the balancer/ pulley from the hub. I have the E4 bit to disassemble the Optispark, just hoping the balancer/pulley comes off relatively easy (only 42,000 miles)!!
I had an old check valve (GM blue and black color from a canister purge valve circa 1983-84) that was plastic I cut the small fitting off one side of the check valve and JB welded it to my Gates WP weep hole, it press fit in perfectly.
I ran a clear silicone hose from the fitting (zip tie around the hose) down the front of the engine passenger side and made a small bracket along with zip ties to keep it from hitting anything that moves.
Good luck with your project
I actually got a cap and rotor kit from Rockauto, it was OEM GM and the box had USA on it!
It is all apart in my garage (second go around) I just need to remove the balancer/ pulley from the hub. I have the E4 bit to disassemble the Optispark, just hoping the balancer/pulley comes off relatively easy (only 42,000 miles)!!
I had an old check valve (GM blue and black color from a canister purge valve circa 1983-84) that was plastic I cut the small fitting off one side of the check valve and JB welded it to my Gates WP weep hole, it press fit in perfectly.
I ran a clear silicone hose from the fitting (zip tie around the hose) down the front of the engine passenger side and made a small bracket along with zip ties to keep it from hitting anything that moves.
Good luck with your project
I will go Rock Auto next time. Corvette Central is taking forever. They were a bit cheaper, but not worth the wait. $50 part but $10 shipping, and order placed Saturday didn't ship until Tuesday. Rock Auto has been awesome to deal with. Plugs and wires are coming from them.
Good idea with the fitting. I am staring down the harmonic balancer now too. It's been soaking in PB Blaster for days now, but last night I couldn't break loose a bolt. It's a pain to get a wrench in there behind the frame & power steering rack.
I am afraid to ask, what is an E4 bit?
I couldn't get a socket on the belt tensioner, so I just pulled the belt off by hand. Getting it back on will be interesting.
With the pump out of the way, it doesn't look like much water made it onto the opti. Dry and grungy. Boy was that pump shot. Bearing retainer was completely blown out and coolant was pouring from the bearing cavity.
I will go Rock Auto next time. Corvette Central is taking forever. They were a bit cheaper, but not worth the wait. $50 part but $10 shipping, and order placed Saturday didn't ship until Tuesday. Rock Auto has been awesome to deal with. Plugs and wires are coming from them.
Good idea with the fitting. I am staring down the harmonic balancer now too. It's been soaking in PB Blaster for days now, but last night I couldn't break loose a bolt. It's a pain to get a wrench in there behind the frame & power steering rack.
I am afraid to ask, what is an E4 bit?
I couldn't get a socket on the belt tensioner, so I just pulled the belt off by hand. Getting it back on will be interesting.
With the pump out of the way, it doesn't look like much water made it onto the opti. Dry and grungy. Boy was that pump shot. Bearing retainer was completely blown out and coolant was pouring from the bearing cavity.
Good luck to you as well!
The E4 bit is needed if you intend on pulling your opti apart (changing cap and rotor or internal inspection of it). Harbor freight had a set for like $9.99 plus a coupon you can find on line for20%.
It was a pain getting at the three bolts, I used a breaker bar on one bolt and a regular socket wrench on the bolt next to it. The I moved on to the last bolt. The hardest part is turning the crank to get the last bolt out of the way of the frame and rack.
I will give my balancer/pulley a small tap (not on the outside ring) and see if it comes off if not I will shorten a 3 jaw puller or maybe a 2 jaw puller to get in there. I don't like smacking on a crankshaft not good for the bearings or anything else for that matter.
Yes, my water pump was shot around the bearing retainer too the weep hole puked and so did the bearing area. My opti was pretty wet on the outside, I guess I will find out how bad it is on the inside soon enough.
You need a good back (I don't have) and patience ( I do have) to work on these cars and a few beers (one left) when you finish the job (just don't go for a test drive after the beers) .
When you need to turn the crank, just put the car in 6th gear (all us lucky ZF6 guys) and you can easily push the car back & forth and the engine turns pretty easy. If you have it up on stands or a lift with the wheels off the ground, it isn't that hard to turn the rear wheels by hand either. (as long as your posi isn't shot.)
They used a multi tooth wheel and a magnetic pick up. Their ignition system shares nothing w/ours. Keep in mind; Indmar used their own proprietary ECM, so they didn't need to use any GM systems. They could use any ignition they wanted to. Also, Timing control isn't as critical in a boat as operating temps are much lower, with an abundance of cold water. You could convert any LT1 over to the Indmar hardware, and people have done it. Hard to get parts though.
If you want to get into it, Indmar part number 536050
It's a pity Chevrolet didn't go this route instead of going with the Opti. Another case of "it seemed like a good idea to somebody at the time," I suppose.
And as an engineering exercise, I suppose a case could be made that it was worth taking a look to see just how well a distributor could be optimized. But, given that distributorless ignition systems were already in use (on Corvette, no less), it should have been clear that distributors were on the fast track to the dustbin of automotive history, and it seems like a foolish decision by engineering management to put this thing into production. If the LT5's ignition system was good enough for the supercar ZR1, it could easily have been recognized that it should have sufficed for the LT1 and LT4.
Now, we get to live with it. At least it's great when it's working as it should.
When you need to turn the crank, just put the car in 6th gear (all us lucky ZF6 guys) and you can easily push the car back & forth and the engine turns pretty easy. If you have it up on stands or a lift with the wheels off the ground, it isn't that hard to turn the rear wheels by hand either. (as long as your posi isn't shot.)
08-07-2016, 07:53 AM
It was the friggin weep hole, not the hose. How did I find out? I wanted to get mine out of the garage post haste in order to start on the wife's '95. Bad move. So I drained and flushed, pulled both knock sensors, replaced "bad" hose and refilled.
Dry and grungy. Boy was that pump shot. Bearing retainer was completely blown out and coolant was pouring from the bearing cavity.
