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You guys are good! I just put a vacuum pump on mine and blocked off the intake side. You can't pull vacuum on it! Is my opti broken? Should I go ls1?
Something has failed, because a vented opti is supposed to be fairly well sealed aside from the controlled venting. Otherwise it would be a vacuum leak. It is supposed to get all fresh air from the intake tract post MAF.
Something has failed, because a vented opti is supposed to be fairly well sealed aside from the controlled venting. Otherwise it would be a vacuum leak. It is supposed to get all fresh air from the intake tract post MAF.
Originally Posted by hrcslam
Yes and yes. It's physics, you need an LS1....
Seriously though, it means that it's not sealed and that should be addressed before it gets damaged.
Go do it, take a vid for me showing vacuum. Pull vacuum with a pump. Both of you. I can wait. How is it not a vacuum leak with the fresh air hose in front of the throttle body? The maf meters the air?
looks like "your" opti cap is not vented...what brand Opti
a vented opti cap should look like pics below
the cap nipple goes to the vent hose that runs to your intake duct after MAF. That hose should have a blue plastic 90 degree fitting that goes into intake duct
The fresh air comes from the port in the intake tract post MAF so that the air pulled through by the manifold vacuum is not a vacuum leak.
I don't know why you are circling something involving the A.I.R. injection. We are discussing the opti venting.
What we are saying is that if there was a problem with the fresh air feed and proper sealing of the opti it can manifold vacuum can build in the opti. I have done it on purpose and if you plug the fresh air line the vacuum in the cap makes it easy for the spark to jump longer distances like to another terminal or carbon tracking.
A 92-93 opti base may not seal even if upgraded to a vented cap setup.
You guys are good! I just put a vacuum pump on mine and blocked off the intake side. You can't pull vacuum on it! Is my opti broken? Should I go ls1?
Tried this today, with the weatherpak connector not connected it leaks like a seive but with the weatherpak in place I used second vehicle to pull a vacuum on one not turning and not only will it pull a vacuum but when you kink the vacuum line and remove it from it's source it will hold a vacuum for an surprising amount of time. Far as collapsing a vacuum line I used a piece of silicon fish tank air line to connect to the running engine and at 18" it did not collapse. Stock line is better than that.
looks like "your" opti cap is not vented...what brand Opti
a vented opti cap should look like pics below
the cap nipple goes to the vent hose that runs to your intake duct after MAF. That hose should have a blue plastic 90 degree fitting that goes into intake duct
Believe it or not, it was an AC Delco which I paid $400 for from summit....
I have a delphi on now which has the correct vented cap. I am running the vacuum lines as you have all recommended.
I got caught up doing bearings on my dd yesterday, but today I had a chance to go tear everything down for the 4th time. Dowel pin is actually just .380", so definitely not too long. Is it possible that it is too short? You can see the marks in the opti in the pictures I posted earlier where it goes "most" of the way down the groove...
Here are a few pictures of the cam and timing cover area:
So if the pin isn't too long, the vacuum lines are run correctly, what am I left with? Could it somehow be an uneven/unbalance cam? Dowel too short or not straight?
I have seen guys with poorly built motors have a lot of hard to diagnose opti issues. Never enough info to figure out if it was funky harmonics breaking the plastic rotor welds or just incompetence.
I might try an MSD cap kit on the current base.
Some guys have literally pop riveted the rotor together with stock rotors before the MSD came out.
The one thing that scares me is that there is a good amount of vibration when I get on it. I imagine to some degree that is normal but it does make me wonder sometimes if something isn't properly balanced. But I'd hate to tear down the whole motor chasing an opti failure.
Also, I'm not sure if this is relevant to anything, but the long block was purchased from Golen Engines in 2003, but since then only has ~500 miles on it. Looking at the car mileage and receipts, it basically was not driven for about 10 years. When I got the car, the oil was low and completely black. I wonder if something in the engine is a bit "gunked up" or something which is causing vibration which in turn is putting a lot of strain on the optispark rotor?
Golen is exactly one of the halfassed engine builders you tend to see opti failures in conjunction with.
If the oil is that dirty in 500miles I would look for a massive over fueling issue.
The long block only has 500 miles on it since 2003?? I would be suspicious of an improper break-in. Until recently, it was up to the customer to break in the engine themselves. Now Golen will do it for you if you want. I suggest changing the oil with some 20w-50 Valvoline VR1 conventional racing oil (it's the oil Golen recommends during break-in) and drive it normally for 500 miles. Avoid WOT if you can. Then change it again to a fully synthetic high-weight oil. I'm using Mobil 1 synthetic 15w-50. I know there's Golen horror stories out there but my long block has been going strong for 5 1/2 years and 30,000 not-very-gentle miles.
The vibration could also be an imbalance in the tires or driveshaft. Also remember that your engine is internally balanced front and rear so any weights on the flywheel/flexplate will cause vibration, too.
The one thing that scares me is that there is a good amount of vibration when I get on it. I imagine to some degree that is normal but it does make me wonder sometimes if something isn't properly balanced. But I'd hate to tear down the whole motor chasing an opti failure.
Originally Posted by sofakingdom
Also, I'm not sure if this is relevant to anything, but the long block was purchased from Golen Engines in 2003, but since then only has ~500 miles on it. Looking at the car mileage and receipts, it basically was not driven for about 10 years. When I got the car, the oil was low and completely black. I wonder if something in the engine is a bit "gunked up" or something which is causing vibration which in turn is putting a lot of strain on the optispark rotor?
OK now you say the engine vibrates, has 500 mi on it, was parked for 10 tears and the oil was low and black....and it was a Golen engine
a engine that "vibrates" (assuming this vibration is a engine source vibration, not driveline) may cause rotor screws to come out causing rotor to wobble and scrape cap.
Golen would have built a "internal" balance motor so if the car has a weighted Flexplate or FW it will shake like a dog shiating razor blades.
More likely, given your vac harness was not functioning properly, your Opti problem was due to that. Certainly fix that part
With that said you need to resolve whatever is causing this "vibration". so as mentioned check your FW/Flexplate
and FWIW I also have a Golen 383 short block and for 9 years, 40k mi and 6400 rpm shifts no "vibrations". Not saying another motor from them could not have issues but given the long sitting time, black & low oil and who know what the PO did on install & break-in. A vulnerably any builder has who sells "customers" short or long blocks when the builder has no involvement in install, break in let alone use conditions.
The fresh air comes from the port in the intake tract post MAF so that the air pulled through by the manifold vacuum is not a vacuum leak.
I don't know why you are circling something involving the A.I.R. injection. We are discussing the opti venting.
What we are saying is that if there was a problem with the fresh air feed and proper sealing of the opti it can manifold vacuum can build in the opti. I have done it on purpose and if you plug the fresh air line the vacuum in the cap makes it easy for the spark to jump longer distances like to another terminal or carbon tracking.
A 92-93 opti base may not seal even if upgraded to a vented cap setup.
It was a pic from google. I circled nothing.
Originally Posted by 96capricemgr
Tried this today, with the weatherpak connector not connected it leaks like a seive but with the weatherpak in place I used second vehicle to pull a vacuum on one not turning and not only will it pull a vacuum but when you kink the vacuum line and remove it from it's source it will hold a vacuum for an surprising amount of time. Far as collapsing a vacuum line I used a piece of silicon fish tank air line to connect to the running engine and at 18" it did not collapse. Stock line is better than that.
Where's my vid? Did you kink the fresh air intake side too?
Was there some sort of check valve? I don't understand how the fresh air side held vacuum when its open to atmosphere. I must be misunderstanding. Yes, everything was connected but I do have some ebay harness from a few years ago.
Was there some sort of check valve? I don't understand how the fresh air side held vacuum when its open to atmosphere. I must be misunderstanding. Yes, everything was connected but I do have some ebay harness from a few years ago.
If you kink the fresh air hose and the vacuum line is still hooked up it should pull a vacuum on the Opti.
I put a gauge on the fresh air side and applied vacuum to the vacuum side. No check valves or anything.
Under normal circumstances there shouldn't be vacuum buildup because the fresh air side will feed more,than the vacuum side pulls.
You guys are good! I just put a vacuum pump on mine and blocked off the intake side. You can't pull vacuum on it! Is my opti broken? Should I go ls1?
10-31-2014, 06:33 PM
