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Spent a good day on the motor and the lesson I've taken is to never throw anything away until it's running again..thankfully I didn't!
Put the original cam back in, sussed out that both means of valve timing work but can't be mixed. Split the timing chain again and managed to derailed off the crank sprocket so 1 hr spent getting it meshed again with tig welding rods.
Refitted the original (cleaned and calibrated) Solex back in place of the new 32/36. Found #2 new spark plug defective so refitted original Bosch super 4s. Ignition retimed to spec.
The engine is purring after fune tuning the solex. Further to the wild vacuum readings taken on Thursday with the Isky cam which pointed to failed head gasket I now have a steady 20 hg at idle with the original cam back in.
In one of my earlier posts on this thread, i wondered how the 32/36 was able to supply enough air to the engine as mine seemed air starved at idle with max 1.5 turns on the idle speed screw. The only way I could keep mine running was to wind the 32/36 idle screw in to max which uncovered the enrichment ports resulting in wet plugs.
At various stages today, I also ran compression tests. These surprised me big time but backed up my initial thoughts with the 32/36 that the motor was air starved with this carb. The results were the same cold or hot - 190 - 200 psi dry. Still finding these reading surprisingly high for a petrol motor.
Anyway, the expensive conclusion have come to is that the 32/36 carb and Isky 66 combo cam are not compatible with my 1900 SH engine.
If this info helps someone in the future, I'll be very happy.
If someone here wants to buy a new Isky 66 combo cam and Weber 32/36 ( I have put in a new power valve after previously trimming the original spring) for a big reduction let me know.
Thanks to all you guys advice and info.
The bottom line is if you’re car is finally running great that’s what’s important, as Jayhawkj already said. Admittedly my first thought was that the cam is now too far advanced, without the degreeing numbers it is an unknown. You would obviously know by loosing the power up top on the rpms. The thing with these engines is the more you take off the cylinder head the higher the compression will be as well as retarding the cam timing, I’m wondering if enough was taken off the head and you advanced the cam one tooth (9.5 degrees, I think) also taking into account what Commdådaren mentioned, could that put you where you’re at on the ccr?

Unless you have a crankshaft with a bit longer stroke than 2.75” 🤷‍♂️ Then that might account for the issues that you had with the combo cam.

Just curious, how is your ignition timing set up now? I assume you’re running premium pump gas, are you experiencing any pinging? What octane gas is available in France?

The 32/36 jetting sounded correct except you should have had a 60 idle jet on the primary.
I’m in the minority but on my stock 1.9 I loved my Solex and had a lot of fun with it while it lasted.

Best of luck just enjoy your success, very happy for you.
 

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Discussion Starter · #42 ·
Thanks.
I am out of time to reply fully at the moment but cam is timed as per Fsm at the moment as is the ignition so could be slightly improved? Fuel is 98 RON and no pre ignition. I bought the car last year in Italy and its history is pretty much a mystery apart from being first owned in Switzerland and spending the last 30 year in a barn so past engine work is unknown. I am still running the new crankbearings and lifters in at the moment so haven't gone above 70% power but the motor finally runs well. The jet numbers between the Solex and the Weber are close but not identical (55 idles). This is the first time I've preferred Solex over a Weber..new ground!
I'll be trying the combo cam and Weber again at some point but want to test the rest of the car fully as its had a 5 month complete strip and rebuild.
 

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OP: This is a long post on the matter of the high cranking compression readings:

For the high cranking compression numbers, and assuming your gauge is as accurate as you think.... the culprit is most likely the behavior of the lifters or the cam timing. What most folks don't realize is that these lifters will leak down even with just modest spring pressure. When that happens, then the cam duration will be much shorter than normal, the intake valve will close earlier on the compression stroke, and the crakning compression numbers will rise.

I cannot tell you with what lifters this will happen but I see all sorts of uncommonly high compression numbers reported on this automotive site in particular. So perhaps the Opel lifters are a bit more leaky than others and getting a new set from OGTS may give you even leakier lifters than the OEM's. (For information, I have carefully measured the leakdown clearance of a GM lifter set bought in 1982 from the Buick dealer and the leakdown clearance is .0004-.0005".) You also need to run the engine for a bit to make sure air in the lifters has all been purged out.

AND using a lighter weight oil (or a synthetic oil when cold) or heavier valve springs will allow/cause more and faster bleeding down of the lifters and thus more likley cause inaccurate high compression reading issues.

Running the compression readings with the engine having been run for 1-2 minutes (to pump up the lifters) but then shut off so the oil is still cold, will probably give you the best results. But even then, I have noticed these lifters sometimes leaking down in a matter of a few 10's of seconds, on a valve/rocker that stops open and with spring pressure on the lifter.

The other possible area is the cam timing.. I am not clear on whether you got rid of that cam timing advance as shown on the cam sprocket picture earlier when you put in the old cam. That was a LOT of cam advance.

The earlier version 19SH has a higher static compression ratio than a stock 19S flat top piston engine, 9,8:1 vs 9,0:1.
You have to realize that the published numbers are not accurate. EVERY manufacturer at that time was exaggerating their static CR but 0.5 to 0.75 points and that include GM and Opel. So 9.0 or 9.1 is real. The published numbers were some sort of 5 sigma production variation that could theoretically occur maybe once in 100,000 engines LOL.

So with stock hydraulic 1.9L US cam data, and a 9.1 Static CR, and cam timing at 'neutral' (ICL =110 degrees), your compression readings should be around 150 psi. Your 20" vacuum reading with the stock cam and higher SCR reflects that type of cam; the Euro cam is probably a little bit different but it will not be far off of these numbers. Even with your cam advanced 11 degrees (an approximation from your prior cam sprocket pix), the cranking compression should not be much higher than 160 psi. And all these numbers area at sea level; they will be lower at higher elevations.

Having said all of that.... I too have had unexpected high cranking compression numbers, by 15-20 psi on the last rebuild < 1 year back, with a well measured and detailed engine setup and an Isky Torquer cam that I measured in detail. Normallly, I will predict the cranking compressoin wihtin 5-10 psi accuracy. My main suspect is that I have been using 10W30 synthetic in this last build with more lifter leakdown and thus having a shorter cam lobe duration while cranking than when actually running. (The viscosity of synthetic oil is much less at 60 degrees F than an equivalent 10W conventional oil.) The next suspect is the sloooow ramp shape of the old Isky cam profiles.

So yeah something is amiss in the testing process, and as noted, I suspect the lifters are leaking down a lot, and the oiling system when cranking is not putting pressure up top to pump the lifters back up.
 

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Discussion Starter · #44 ·
OP: This is a long post on the matter of the high cranking compression readings:

For the high cranking compression numbers, and assuming your gauge is as accurate as you think.... the culprit is most likely the behavior of the lifters or the cam timing. What most folks don't realize is that these lifters will leak down even with just modest spring pressure. When that happens, then the cam duration will be much shorter than normal, the intake valve will close earlier on the compression stroke, and the crakning compression numbers will rise.

I cannot tell you with what lifters this will happen but I see all sorts of uncommonly high compression numbers reported on this automotive site in particular. So perhaps the Opel lifters are a bit more leaky than others and getting a new set from OGTS may give you even leakier lifters than the OEM's. (For information, I have carefully measured the leakdown clearance of a GM lifter set bought in 1982 from the Buick dealer and the leakdown clearance is .0004-.0005".) You also need to run the engine for a bit to make sure air in the lifters has all been purged out.

AND using a lighter weight oil (or a synthetic oil when cold) or heavier valve springs will allow/cause more and faster bleeding down of the lifters and thus more likley cause inaccurate high compression reading issues.

Running the compression readings with the engine having been run for 1-2 minutes (to pump up the lifters) but then shut off so the oil is still cold, will probably give you the best results. But even then, I have noticed these lifters sometimes leaking down in a matter of a few 10's of seconds, on a valve/rocker that stops open and with spring pressure on the lifter.

The other possible area is the cam timing.. I am not clear on whether you got rid of that cam timing advance as shown on the cam sprocket picture earlier when you put in the old cam. That was a LOT of cam advance.

You have to realize that the published numbers are not accurate. EVERY manufacturer at that time was exaggerating their static CR but 0.5 to 0.75 points and that include GM and Opel. So 9.0 or 9.1 is real. The published numbers were some sort of 5 sigma production variation that could theoretically occur maybe once in 100,000 engines LOL.

So with stock hydraulic 1.9L US cam data, and a 9.1 Static CR, and cam timing at 'neutral' (ICL =110 degrees), your compression readings should be around 150 psi. Your 20" vacuum reading with the stock cam and higher SCR reflects that type of cam; the Euro cam is probably a little bit different but it will not be far off of these numbers. Even with your cam advanced 11 degrees (an approximation from your prior cam sprocket pix), the cranking compression should not be much higher than 160 psi. And all these numbers area at sea level; they will be lower at higher elevations.

Having said all of that.... I too have had unexpected high cranking compression numbers, by 15-20 psi on the last rebuild < 1 year back, with a well measured and detailed engine setup and an Isky Torquer cam that I measured in detail. Normallly, I will predict the cranking compressoin wihtin 5-10 psi accuracy. My main suspect is that I have been using 10W30 synthetic in this last build with more lifter leakdown and thus having a shorter cam lobe duration while cranking than when actually running. (The viscosity of synthetic oil is much less at 60 degrees F than an equivalent 10W conventional oil.) The next suspect is the sloooow ramp shape of the old Isky cam profiles.

So yeah something is amiss in the testing process, and as noted, I suspect the lifters are leaking down a lot, and the oiling system when cranking is not putting pressure up top to pump the lifters back up.
Hi MR
Yes, it is a long thread but all input from you guys is great and appreciated. I noted the comparatively weak spring pressure on the new refurbed lifters when the I fitted them first off with the Isky. When I first ran the motor with the problems that I had, I also noted the fast leakdown even though I am running 20/50 mineral with breakin additive. As I said, I don`t have the time to play with it at the moment but I`m a tenacious guy so will be diagnosing further when time allows. The motor is running well now but I feel it could be optimised. I will also refit the (rejetted) Weber again and see how that behaves. In the meantime I have to prep for 3 months of Opelling in Mallorca. If anyone on here is over that way, maybe a island tour could be in order??
Thanks again.
 

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A note: If you are talking about the weak spring pressures being the pressure for the lifter plunger inside the lifter body, that normally does not come into play for leakdown. That spring is there to provide some force to push the plunger up and close any slack or gaps in the valvetrain when the lifter is on the heel of the cam lobe. (I.e., valve is closed.) So that internal spring pressure is not critical... unless it is very weak. The hydraulic lifters will leak down a few thousandths of an inch during each lift cycle when running. With a very weak internal spring there may not be enough time to close the resulting valvetrain gap each lift cycle. But I would not think that is a problem for the slow engine speed during cranking.

Excess leakdown is either from the check ball not closing well (like for a misshaped ball) or from the plunger to body clearance being too large. It seems that you should have been in good shape for leakdown with that 20W50 mineral oil.

Have a good time in Mallorca!
 

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Discussion Starter · #46 · (Edited)
A note: If you are talking about the weak spring pressures being the pressure for the lifter plunger inside the lifter body, that normally does not come into play for leakdown. That spring is there to provide some force to push the plunger up and close any slack or gaps in the valvetrain when the lifter is on the heel of the cam lobe. (I.e., valve is closed.) So that internal spring pressure is not critical... unless it is very weak. The hydraulic lifters will leak down a few thousandths of an inch during each lift cycle when running. With a very weak internal spring there may not be enough time to close the resulting valvetrain gap each lift cycle. But I would not think that is a problem for the slow engine speed during cranking.

Excess leakdown is either from the check ball not closing well (like for a misshaped ball) or from the plunger to body clearance being too large. It seems that you should have been in good shape for leakdown with that 20W50 mineral oil.

Have a good time in Mallorca!
Yeah, all noted. I suppose this is why they recommend adjusting with the motor running and a splash guard fitted. I may give that method another go just to double check I have mine correct.
Thanks, M R.
 

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I used an Isky Ultra Comp for some rallying and others, and always just did the process of making sure the lifter was no the heel of the cam lobe and then turned the adjusting nut 3/4 turn after the valvetrain slack was taken up. Never had any issues. Adjusting up or down won't change a leak down issue anyway, unless the adjustment is such that almost all of the internal plunger movement is eliminated. (Which is what is done in some performance designed lifters that have very little plunger movement... meant to solve a different problem.)

FWIW.... I recently changed the oil in my engine from 10W30 semi-synthetic Joe Gibbs oil to 15W50 Mobil 1 full synthetic. I was chasing a vexing problem of noisy hydraulic lifters, a problem that I had never had before. The lifters initially were rebuilds from OGTS and I went through them to tighen up the leakdown clerances as described above. That did not fix the issue, but just eliminated one possible problem. I then changed to an OEM set of almost new lifters I have had from almost 40 year ago, sitting around in the original box. Again, not a big difference. When the oil change was made 15W50, that made a BIG reduction in lifter noise. The engine now sounds like a normal Opel engine 'back-in-the-day' when 10W40 Castrol GTX was my go-to oil weight and type. The engine even runs more smoothly. So the oil weight is making a notable difference in the leakdown rate per-lift-cycle. How much difference it makes in the leakdown rate of the lifters in the slow cranking speed for a compression test, I have not checked yet. I figure that the 15W synthetic at cold start temps is of a similar viscosity as a 10W petroleum oil.

By the way, the valve springs are heavier than stock so that is part of what I have been fighting with the lifter noise.
 

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Yeah, all noted. I suppose this is why they recommend adjusting with the motor running and a splash guard fitted. I may give that method another go just to double check I have mine correct.
Thanks, M R.
The procedure of adjusting the valves on a CIH engine while it is running (and requiring a chain splash cover) is ONLY for an engine with solid lifters. Adjusting valves on a CIH engine with hydraulic lifters is performed with the engine shut off, hot or cold.
 

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It works exactly as good for the hydraulic lifters as for the solid ones. On my CIHs the valves are always adjusted with the engine running, hydraulic or solid.
 

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The procedure of adjusting the valves on a CIH engine while it is running (and requiring a chain splash cover) is ONLY for an engine with solid lifters. Adjusting valves on a CIH engine with hydraulic lifters is performed with the engine shut off.
Doing it while running really is unecessary for the hydrualics. The standard objective of the hydraulic adjustment is to get the plunger positioned to where it is approximately in the middle of the plunger's travel range within the lifter body, when the valve is closed. The fixed '3/4 turn adjustment' does that just fine.

The only reason I would adjust the hydraulics running is if I was trying to make a different type of adjustment, like maybe getting the plungers just barely within the upper end of their travel range with the valve closed (like if you were trying to avoid excess lifter pump-up if the valves floated). But most uses don't need that type of adjustment.
 

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It works exactly as good for the hydraulic lifters as for the solid ones. On my CIHs the valves are always adjusted with the engine running, hydraulic or solid.
Hey C, what procedure do you follow with the hydraulics when running? Do you make the 3/4 turn after getting them tight enough to be quiet? Just curious as to where the adjustment is ending up. That process when running does have the advantage of not having to make sure each lifter is on the heel of the cam lobe when adjusted, but I am too lazy to bother controlling the mess....
 

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I’ve attempted adjustment to the lifters while running (hydraulic), made a splash guard out of an old valve cover, no problem with the oil control but perhaps someone can elaborate on the set up. I couldn’t tell where my rocker arms were because I didn’t really understand the procedure. Do you start at zero lash on hydraulic lifters and keep it between zero & one turn before you start the engine running?
 

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No need to do all that....I usually just rotate a fresh engine and take all the slop out of any lifter as I notice them. (any valve)...then start the engine...it will start with just that rough adjustment...then tighten each lifter until the clack just goes away...I do that procedure several times as at first it is hard to tell which one is clacking...then slowly I go thru them again...this time I am sure I am working on the clacker...just to the point where the clack goes away...then slowly an additional 3/4 of a turn... Did I answer your question ?
 

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Hey C, what procedure do you follow with the hydraulics when running? Do you make the 3/4 turn after getting them tight enough to be quiet? Just curious as to where the adjustment is ending up. That process when running does have the advantage of not having to make sure each lifter is on the heel of the cam lobe when adjusted, but I am too lazy to bother controlling the mess....
First an initial adjustment to start the engine and then loosen the nut until the rocker starts to clatter, after that tighten the nut again until the clatter goes away, and the last step is tightening the nut one full turn in 90° increments with a pause between each one to stabilize the idle.
 

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No need to do all that....I usually just rotate a fresh engine and take all the slop out of any lifter as I notice them. (any valve)...then start the engine...it will start with just that rough adjustment...then tighten each lifter until the clack just goes away...I do that procedure several times as at first it is hard to tell which one is clacking...then slowly I go thru them again...this time I am sure I am working on the clacker...just to the point where the clack goes away...then slowly an additional 3/4 of a turn... Did I answer your question ?
I want to ask, is it that obvious if you’re too tight? Does the engine sputter obviously or is it more subtle? That’s always been what’s backed me off from this proceedure. As I understand it that’s the surest way to burn up a valve. Sorry if I’m hijacking, one last good answer and I’ll stop, I promise. Thank you
 

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First an initial adjustment to start the engine and then loosen the nut until the rocker starts to clatter, after that tighten the nut again until the clatter goes away, and the last step is tightening the nut one full turn in 90° increments with a pause between each one to stabilize the idle.
Minus the difference between 3/4 vs one full turn, this is exactly what Gil from OGTS told me

That said, I've always done my valve engine off...
 
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Hey C, what procedure do you follow with the hydraulics when running? Do you make the 3/4 turn after getting them tight enough to be quiet? Just curious as to where the adjustment is ending up. That process when running does have the advantage of not having to make sure each lifter is on the heel of the cam lobe when adjusted, but I am too lazy to bother controlling the mess....
I tried it long ago by ear, my problem is I went back & forth on them so many times chasing the noise I lost complete track of where the final adjustment was. Not really knowing what in the devil I was doing, afraid of being too tight and burning up a valve with all those valves moving so fast and quite honestly nothing being very quiet I just gave up and did it as described below.

Since then usually with the engine cold, I never really could tell any difference : -)
On assembly I just install everything, tighten up the rockers with the lifters riding on the base of the lobe . To adjust using the same method being sure it’s riding on the base. I measure up the zero lash by using a very thin feeler gauge .04mm, get a very slight drag (hardly noticeable) between the valve & rocker then anywhere from 1/2 to 3/4 turns after contact looking for any plunger movement on the lifters while setting it up. Usually the spring pressure on the plunger is enough to cause obvious drag between the rocker & valve with that thin of a feeler gauge. I’ve always been anal about keeping them all exactly the same, keeping them short of that full turn where I’ve heard that the wear spot on the lifters sits there from the original factory set up.
 

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First an initial adjustment to start the engine and then loosen the nut until the rocker starts to clatter, after that tighten the nut again until the clatter goes away, and the last step is tightening the nut one full turn in 90° increments with a pause between each one to stabilize the idle.
That sounds like an very good procedure, C, and gets the plunger into the mid range of it travel. Tnx.
 

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Since then usually with the engine cold, I never really could tell any difference : -)
And really it should not make any difference. The whole point is to get the lifter plungers approximately in the middle of their travel inside the lifter body, with the valve closed. That total plunger travel is typically in the .120" range or even more for your run-of-the-mill factory hydraulic lifter. That amount of plunger travel can take up a lot of variation in the parts, and you can be pretty sloppy in the adjustment and it'll still work the same. Hence 1 turn or 3/4 turn or 1/2 turn won't matter, and even maybe 1/4 turn! You're moving the plunger by about .015-.018" for each quarter turn. (Computed off the top of my head....)

I’ve always been anal about keeping them all exactly the same, keeping them short of that full turn where I’ve heard that the wear spot on the lifters sits there from the original factory set up.
IDK about any such wear spot at 1 turn...???? The wear spot related to the number of turns on the rocker nut might be on the rocker stud where the nut sets but if you do any valve work, the finished valve tip height is gonna move up or down a bit 99% of the time, and the exact points at which things ride and adjust will change anyway.

Where people might get off when doing this statically is that the rocker ball and pivot will change the zero lash point a bit depending on exactly how the parts line up. I wiggle the rocker as I find the zero lash point to avoid that. (and do that for solid adjustments too. )The running setup does the 'wiggling' for you. But you don't get lost 'finding the noisy lifter' when doing it statically.
 

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It works exactly as good for the hydraulic lifters as for the solid ones. On my CIHs the valves are always adjusted with the engine running, hydraulic or solid.
If it works for you, and if the result is a lifter that is accurately adjusted such that the lifter plunger is partially depressed, and not bottomed out, and since it is your engine, then no worries.

One issue I have encountered on brand new hydraulic lifters is that they are SO leak-down proof that they do not allow oil to be expelled from the lifter cavity when the adjusting nut is tightened. If so, they act like a solid lifter, and tightening causes the valve to un-seat. The solution is to pull each lifter out just before the rocker is adjusted, and carefully depress the plunger in a vice, expelling the trapped oil. Then install the lifter, and adjust using the correct method. Within a few hours of operation, the lifter will adjust properly.

For clarity, there is no reason (none, nada, zilch) reason to adjust hydraulic lifters with the engine running.
 
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