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Just Some Dude in Jersey
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I'm not 100% sure that all CIH engines with the dipstick hole in the block have the internal tube. I had a factory 2.0 engine that was supposed to have it, but it was also missing from my engine. I didn't know it was supposed to be there either until later. I could wiggle the dipstick and feel it rubbing the side of the crankshaft while the engine was running. I had trouble with that engine leaking oil out of the dipstick hole and the stick not fitting good. My 2.4 does have the tube, but, before it was rebuilt, it had the blowby which would slowly push the dipstick out of the block.

Later or this weekend I will take a picture of the tube in my faulty 2.4.
 

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Opel Rallier since 1977
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Discussion Starter #23
Cant' say I ever recall any internal dipstick tube on any 1.9L I have ever taken apart....

And, it would help if I actually included that link for you, TC!
https://www.forabodiesonly.com/mopar/threads/hf-leakdown-test-is-a-piece-of-big-steenkeeng-shtuff-but-here-is.380676/#post-1971683612

Since air is already 78% nitrogen (or something like that), I don't see how it would effect the leak down test all that much.
I just started reading the attachment. Even if the engine is okay it’d Still be kinda nice to know it’s condition. I’m working on plugging the dip stick, already solidly inserted with an o’ring, I noticed the rubber around the dipstick is shot. Time to get a hold of OGTS. I’ll keep reading up tks.
 

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Funny my dip stick is missing a chunk off the bottom half/in half if that makes since waiting for weather to cool down before I ask my buddy to help me at his shop to pull the pan with all the other stuff I need to do from under I just hope it fell outside and not inside when it broke but haven't had an issue with it popping out that seems strange
 
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Discussion Starter #26
Holy cow, almost into the second year after the rebuild, now I it may come back to bite me as things do sometimes when I get all excited after my first run after a repair but the dipstick seems to have been it, there is a vast improvement, it helps to talk this stuff out and get a little encouragement. I just did some hard revs & high rpm decelerating. No odor right now I just took out the dipstick and put it under the drivers seat, I just cut a few inches of 1/2” hose with a cap it fits snugly enough that hose clamps aren’t needed. The dipstick tube was forced in well enough to put some crush on the o’ring. All in all a good seal. Man that’s a stinky crankcase, the Brad Penn zddp oil adds to it I’m sure. I have the 72’-73’ CIH GT dipstick and unfortunately OGTS only has the earlier style. Thank you for sending the one you have Gordo maybe it will work. Well if I am actually there I’ll get back to the conversation of the leakdown topic. So if I have this right between the pressure source and the first gauge is a pressure regulator, between the first and second gauge, this is where it gets confusing for me, is fixed orfice, what size and how long for the 2 liter CIH? It seems that’s a make or break item, without the proper feed on say 100 psi into the second gauge the whole test is not accurate. The 40 thousandths orfice is mentioned so is that the standard that comes in a Harbor Freight kit for instance? What if the orfice is too big, your engine looks great, if it’s too small time for a tear down?
 

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Just Some Dude in Jersey
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Why spoil your victory by chasing a (possible) problem that seems to have no effect on the car? You don't go through oil, now you won't smell it anymore, so, so what if you have a little wind coming out of your engine? I put 225K+ on my previous 2.0 and a nice strong breeze came out of the valve cover the whole time. It didn't affect a thing.

Sleep well tonight, safe in the thought that the normal, musty, dank, stank of your rotting interior will no longer be intruded upon by the dank, musty, stank of your stinky engine oil.

:veryhappy
 

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Opel Rallier since 1977
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As for the LD tester.....The 100 psi source pressure is one standard. There are others, like used in small aircraft piston engines, where the standard test pressure is 80 psi.

What you are really doing is comparing the leakage of the cylinder with the 'leakage' through the orifice, by looking at the relative pressure between the 2 leakage points (i.e., the cylinder pressure) . From your comments, it sounds like you get that. The thread I linked never says what the HF orifice diameter.... I have one and checked... it is around .075"-.080". (2mm is a good guess at what drill they used THAT day in China LOL). So not at all close to 'standard'. And the output pressure gauge tops out at 15 psi input pressure with no output leakage.... so you are testing with 15 psi.....again, nowhere close to standard.

BTW, if you have or can borrow a work type of compressor (like for nails guns), then you can set the feed pressure with its regulator and gauge to 80 or 100 psi. Then move the input gauge on the HF tester (which reads to 100 psi, but with what accuracy.... I do not know) to the output side, and put in a proper orifice. This describes a proper FAA orifice. https://en.wikipedia.org/wiki/Leak-down_tester

BTW, you want to test with the the piston near TDC, preferably with the piston stopped on the upstroke just before TDC. The engine CAN move on you quickly when you put 80 or 100 psi in there; if you put a wrench on there to hold it in place, then hold it FIRMLY or lock it in place somehow. With the piston sizes we have, 100 psi in the cylinder will exert approximately 1000 psi on the piston and could throw a wrench with a sudden movement. (Similarly, testing aircraft engines can be dangerous if you are not careful.... if the prop spins with 80 psi in those larger cylinders, it will really hurt anyone in the way of the prop.)
 

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Discussion Starter #30
Is the smell actually like gasoline, or more of an acrid, oily smell?

Serious suggestion: Have someone drive behind you.... decelerate several times from maybe 50 MPH or down that steep grade and have them look for oil smoke. In between, accelerate hard up through 2nd and 3rd and have them look for smoke under acceleration. (Use hand signals or a cell phone to communicate what you are going to do next.)

Smoke that gets worse during decel will be your intake seals. Smoke under hard extended acceleration is most likely blowby. Make sure the look to see if any smoke is coming from the exhaust pipe, or just from under the car body.

Having someone observe this from behind is a much better way to detect things.
Well the celebration was short lived. I still have the problem. I did the drive test my wife followed first hard deceleration (throttle plates closed) down a steep grade in second she saw smoke coming out the tailpipe, that’s in harmony with the odor I was smelling at the time btw. Next I did my usual WOT to 6500 rpm’s clean as a whistle she said. It seems to be at its worst with the throttle closed or almost closed. It would make sense that I’m not loosing much oil at all since I only hit that scenario probably 5% of the time, it ran clean on the highway and everywhere else she said. I’d like a second opinion but I’m pretty convinced since the back of the intake valve heads look the way they do and the smoke/smell comes in when it does I’m hoping it would be the lesser of the two evils. The leakdown test would mainly focus on the piston rings and valve seatin, correct? Not the stems/guides or seals right? Apparently new guides from OGTS were installed with I think standard 11/32” seals, not the metric seals R Bob said he uses my build thread. How easy are the seals to replace on the car?
 

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Do you have any photos of the cylinder head work ? Opel valves are metric and 11/32 would be incorrect. I will try to post some photos I have soon so you can see what you my need.
Did your machine cut down your valve guide area for posi-lock seals? Seals can be replaced with the cylinder head on the car with the correct tools and skills.
John
 

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I have posted some photos that will help. The first photo is a stock cylinder head showing the valve spring seat area before work.
The second is a head I had machined to install bronze/alloy valve guides and the next is with seals and valves installed.
This would not look like what you have but you should have had the area around the valve guide machined down to be able to install the posi-lock valve seals on the intake valves, but using metric sizes.
If you look at the first photo left-to-right exhaust valve then intake valve is next and the cut down areas would match if your machine shop cut to match exhaust for the seals to grip. Hope this helps.
I can post photos of the tools you would need, to install the seals on cylinder head in the car.
John
 

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I had a blow-by problem on my low mileage rebuild for a number of years. I eventually traced it the the small vacuum line that goes from the valve cover to the intake manifold. The orifice in the fitting at the intake manifold is very small and had become plugged. I wouldn't have believed it, but that little hose is apparently critical, and if it's not working properly the crankcase builds pressure. It's easy to clean. Just take the hose off at the manifold and run a small drill bit through the fitting. I'm just guessing at the drill bit size I used, but it seems like it was very small, maybe 1/16 or 5/64". In my case the fitting was completely plugged and was causing both oil leaks and the crankcase odor you describe. Perhaps yours is only partially plugged? Easy enough to check.
 

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Well the celebration was short lived. I still have the problem. I did the drive test my wife followed first hard deceleration (throttle plates closed) down a steep grade in second she saw smoke coming out the tailpipe, that’s in harmony with the odor I was smelling at the time btw. Next I did my usual WOT to 6500 rpm’s clean as a whistle she said. It seems to be at its worst with the throttle closed or almost closed. It would make sense that I’m not loosing much oil at all since I only hit that scenario probably 5% of the time, it ran clean on the highway and everywhere else she said. I’d like a second opinion but I’m pretty convinced since the back of the intake valve heads look the way they do and the smoke/smell comes in when it does I’m hoping it would be the lesser of the two evils. The leakdown test would mainly focus on the piston rings and valve seatin, correct? Not the stems/guides or seals right? Apparently new guides from OGTS were installed with I think standard 11/32” seals, not the metric seals R Bob said he uses my build thread. How easy are the seals to replace on the car?
In my experience, when you see steady exhaust smoke during deceleration, or a puff of smoke during a gear change when you temporarily close the throttle plates, it is a problem of oil incursion around the intake valve stem.
With the intake valve open, the throttle plate closed and the piston on the downstroke, the extra vacuum created by the engine will try to pull air in from any where it can. A poorly sealed intake valve stem is usually the weak link and it allows extra oil to be drawn into the engine and burned on these occasions.
When the throttle plate is opened as you return to normal cruise, the the extra stress on the intake and seal is relieved and the smoking stops.
 

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Discussion Starter #35 (Edited by Moderator)
Do you have any photos of the cylinder head work ? Opel valves are metric and 11/32 would be incorrect. I will try to post some photos I have soon so you can see what you my need.
Did your machine cut down your valve guide area for posi-lock seals? Seals can be replaced with the cylinder head on the car with the correct tools and skills.
John
Yes I did have the valve guide areas machined, the Chevy type seals I was told would work fine, and please, I’m not trying to drag anyone else into a debate on this subject because I’ve learned there’s mixed opinions on this. With all due respect I’m not trying to offend anyone. I’m not sure if anything was done on the intakes but the exhaust guides were modified so I could go with positive seals all the way across. The umbrellas were also removed otherwise stock springs as previously mentioned OGTS 2 liter valves and guides were purchased and installed by the machine shop.

I don’t seem to be having any problems in this area but he couldn’t install the hardened 2 liter exhaust seats Gil gave me so he installed his own and had them machined into the head to accept the 2.0 exhaust valves. I’m not sure on any more details, for some reason he had a difficult time getting the valves all at the same height by using the OGTS seats, I think he had an issue with the guides on that subject too. The main regret for me was NOT taking the cylinder head to the shop Gil recommended, he tried convincing me, bless him for that.

So if the seals can be changed with the head on, it seems worth doing. If the head would have to come off then that’s another subject for another day. To save the trouble of looking back on my engine build thread I’ll just post the quote from Rally Bob I mentioned earlier on this subject “ Easiest way is to utilize the newer 2.4 CIH engine's metal-clad Viton valve stem seals. OGTS should have them. Not the cheapest, but they do the trick on the 9 mm valves. It's all I use on heads that I retain 9 mm valves on“. So if I’m going through the trouble to try and do this, I’ll install the proper seals that either you have in mind or what I just quoted from Bob when they’re available. For the record I did check into getting the ones Bob mentioned back then and they weren’t available at the time. I have no idea how to do it yet but willing to give it a try, the standard spring compressors won’t seem to work, from what I remember one of the idea’s that might work is to put pressure underneath the valve with stuffing rope in the combustion chamber, compressed air or something like that (piston at TDC on the compression stroke) and push down on the top of the spring using a tool with a hollow center that will allow the spring to compress enough to get the keepers out, but getting them back in this way certainly doesn’t sound easy. I’m looking forward to seeing or hearing about any tools or words of advice on doing this. As far as pictures here’s a few but none without the springs, I’m not quite sure if what you’re looking for will be there.

Thank you for your input.
 

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Opel-spec valves have 9 mm stems, both stock 1.9 or 2.0 valves. The seals that you describe aren't "Chevy type", but are called "positive seals" and are common in the industry. However, it is common practice to use Chevy valves in place of Opel valves, to get bigger valves much less expensively. That requires the guides (and stem seals) to be changed to 11/32" (and I believe that the seal guide post also has to be machined to an imperial dimension, and not metric, and are therefore NOT interchangeable). 11/32" is only 8.73 mm, and I don't believe that a 11/32" valve stem seal will even fit over a 9 mm valve stem.

Non-Opel-spec valve seats are not an issue, and it is common to use standard industry seats with Opel valves.
 

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The KD912 compressor tool will work with the head on the car. Not the best angle on the handle for an I4 engine (that toll is made for a V8) but you can find them cheap on eBay. Use the rope in the cylinder as you mentioned. Stock seals will do better than you seem to think.

Symptoms match the gunk on the valves. Give your wife kudos for a good eye! The odd part though is that you smell this inside the car. So I am not 100% certain this is all solved. Maybe your tailpipe tip sits at a location where the exhaust gets sucked back in at certain times? But start with the new seals and see where this goes since it is not a lot of work.
 

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Just Some Dude in Jersey
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Do you still want me to send you that dipstick? It sounds like you've got issues that could culminate in a rebuild. Possible excessive blowby, valve stem and sealing issues, etc. Normally I would preach doom and gloom to you, but my recent engine issues now make me question everyone's rebuild.

:sigh:
 

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Discussion Starter #39
Do you still want me to send you that dipstick? It sounds like you've got issues that could culminate in a rebuild. Possible excessive blowby, valve stem and sealing issues, etc. Normally I would preach doom and gloom to you, but my recent engine issues now make me question everyone's rebuild.

:sigh:
No Gordo, please don’t bother at this point. Hope I’m not too late. Thank you for your offer.
 

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Discussion Starter #40
The KD912 compressor tool will work with the head on the car. Not the best angle on the handle for an I4 engine (that toll is made for a V8) but you can find them cheap on eBay. Use the rope in the cylinder as you mentioned. Stock seals will do better than you seem to think.

Symptoms match the gunk on the valves. Give your wife kudos for a good eye! The odd part though is that you smell this inside the car. So I am not 100% certain this is all solved. Maybe your tailpipe tip sits at a location where the exhaust gets sucked back in at certain times? But start with the new seals and see where this goes since it is not a lot of work.
I’m with you on that, If the seals are easy to replace I’ll try that first.
To back track here. Is is jumping the gun to say that the problems are centered with the cylinder head, not the rings? I’d be very happy to rule the piston rings out :veryhappy

As for the odor, it seems that it’s when a window is open it’s pulling the fumes from the engine bay through the fresh air vents. This doesn’t happen with the windows closed, I suppose that the odor just goes elsewhere. This appears to be coming from the valve cover or crankcase. Since the engine is running smoothly I can assume it’s not going back through the carburetor.
Could the events Spring GT describes in post #34 be enough to cause that? I have a brand new 2” exhaust. I’ll be glad to send pictures if that helps.

My intake manifold vent to the small hose is clear, that’s where I pick up my vacuum readings from. Currently a steady 18” @ idle.

MR I don’t know how to use the valve spring removal tool you mentioned can you please describe to me a bit more how you go through this procedure? Depending on its difficulty level I’m game for trying that first and seeing where things are afterwards.

Thank you again.
 
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