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  #121 (permalink)  
Old 06-26-2012, 06:21 PM
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Quote:
Originally Posted by lt1silverhawk
I think for the sake of safety and ease of work, I will look for a quality compressor. The one the the guy uses in the video, a Proform brand, seems pretty good so I'll look for that one. Although the valve holder tool isn't expensive ($10 on Amazon), I definitely appreciate the tip on the clothes line.



Btw, are the diameters for the seals pretty much the same, or will it vary by motor? I tried looking them up on Summit and they have several different diameters for an SBC. The reason I am concerned is that this engine is a crate engine, so I am not sure if it would be the same as the one for a stock motor in a '77 Chevy.
First, some clarification.
Quote:
Originally Posted by cobalt327
Cloths line can be used through the plug hole to wedge the valve closed for removal so a compressor isn't necessary.
The compressor in the quote is an air compressor, not a spring compressor, which is still needed (a spring compressor, that is).

I am thinking you will have the small O-rings that seal the retainer to the valve stem. This set up uses a tin oil shield under the retainer.

I found a page here that shows the same spring compressor I have used successfully on stock SBC springs a number of times. It's inexpensive as well. The seals, retainers, locks, oil shields and O-rings shown there are what you will have- I think.

If you have 'positive' seals that are pressed onto the OD of the guide boss, they do come in several different ID and OD. But see what you have (small O-ring or positive type) and we can go from there.

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  #122 (permalink)  
Old 06-26-2012, 06:45 PM
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Tranny fluid in the vacuum hose means its getting sucked by the engine past the modulator. The modulator would require replacement.
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  #123 (permalink)  
Old 06-26-2012, 08:15 PM
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Quote:
Originally Posted by cobalt327
First, some clarification.
The compressor in the quote is an air compressor, not a spring compressor, which is still needed (a spring compressor, that is).
I knew what you meant, but thanks for the clarification.




Quote:
Originally Posted by cobalt327
I am thinking you will have the small O-rings that seal the retainer to the valve stem. This set up uses a tin oil shield under the retainer.

I found a page here that shows the same spring compressor I have used successfully on stock SBC springs a number of times. It's inexpensive as well. The seals, retainers, locks, oil shields and O-rings shown there are what you will have- I think.

If you have 'positive' seals that are pressed onto the OD of the guide boss, they do come in several different ID and OD. But see what you have (small O-ring or positive type) and we can go from there.
Ok, time to remove a valve cover and do some digging. Thanks for the link. I will compare what my engine has to the one on that page.




Quote:
Originally Posted by 123pugsy
Tranny fluid in the vacuum hose means its getting sucked by the engine past the modulator. The modulator would require replacement.
Got it. I imagine it wouldn't make much of a difference if the truck hasn't been started in over a week?
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  #124 (permalink)  
Old 06-27-2012, 02:15 AM
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Quote:
Originally Posted by lt1silverhawk
I knew what you meant, but thanks for the clarification.





Ok, time to remove a valve cover and do some digging. Thanks for the link. I will compare what my engine has to the one on that page.





Got it. I imagine it wouldn't make much of a difference if the truck hasn't been started in over a week?
No diff- hose and modulator vacuum port has to have zero ATF in it.
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  #125 (permalink)  
Old 06-27-2012, 08:57 AM
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I inspected the vacuum line at the intake as well as the modulator. It was dry at the intake, but covered in oil externally at the modulator (along with surrounding parts). And although I've tightened it it up before at the modulator, the small rubber hose was a bit loose again. I removed the small rubber hose connecting the modulator to the metal line and found no ATF inside.


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  #126 (permalink)  
Old 06-27-2012, 09:15 AM
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You got to get those oil leaks under control.

The oil is making your vacuum hose gooey.
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  #127 (permalink)  
Old 06-27-2012, 09:30 AM
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Quote:
Originally Posted by lt1silverhawk
I inspected the vacuum line at the intake as well as the modulator. It was dry at the intake, but covered in oil externally at the modulator (along with surrounding parts). And although I've tightened it it up before at the modulator, the small rubber hose was a bit loose again. I removed the small rubber hose connecting the modulator to the metal line and found no ATF inside.
No ATF is a good sign, but the piece of rubber tubing needs to be replaced w/new rubber tubing, not the old hardened or mushy-from-ATF piece that's on there now that's taken a set. Use a long enough piece that it's not pulling the hard line when connected, but not SO long that it crimps shut from any bends that you might need to put in it. Straightening the hard line so that it's directly in line w/the modulator vacuum port will help matters. I think we discussed this previously.
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  #128 (permalink)  
Old 06-27-2012, 11:46 AM
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Quote:
Originally Posted by 123pugsy
You got to get those oil leaks under control.

The oil is making your vacuum hose gooey.
I know, and its bugging me that I can't find this leak. I've tried everything from wiping down everything to keeping a tray under the truck to figure out where its all coming from. I swear there is a Bermuda Triangle behind the engine where bolts disappear and oil mysteriously leaks.




Quote:
Originally Posted by cobalt327
No ATF is a good sign, but the piece of rubber tubing needs to be replaced w/new rubber tubing, not the old hardened or mushy-from-ATF piece that's on there now that's taken a set. Use a long enough piece that it's not pulling the hard line when connected, but not SO long that it crimps shut from any bends that you might need to put in it. Straightening the hard line so that it's directly in line w/the modulator vacuum port will help matters. I think we discussed this previously.
Yes, you did bring this up on page 2. I've actually been meaning to remove the metal line as well and inspect it for any damage, but it became quite obvious today it won't be an easy task. I'll be replacing the rubber portions soon.
Quote:
Originally Posted by cobalt327
That vacuum line to the modulator valve- bend the hard line so it's pointing directly at the valve so the rubber hose connection is straight. It might be the photo, but the hose looks like it's becoming delaminated where it's bent. If there is any question, replace that length of rubber hose w/a new piece.


I will take another look at the spark plugs' electrodes next to see if there is any discoloration. I will also replace every vacuum hose as well as the PCV valve and grommet. I'll try to get to the valve stem seals this weekend.
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  #129 (permalink)  
Old 06-27-2012, 10:09 PM
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I wouldn't remove the hard vacuum line to the modulator. Instead, cap one end and draw a vacuum on the other end. If the vacuum holds- and the line is clear- (no kinks or obstructions, check for this by blowing through it or pull a vacuum unplugged, it shouldn't hold), it's OK.

Some modulator lines went to a fitting on the intake that had a small orifice that acted as a sort of delay valve. If you still are using one like this, be sure the orifice isn't clogged up w/carbon, etc., or the tranny might shift weird.
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  #130 (permalink)  
Old 06-28-2012, 12:04 AM
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Quote:
Originally Posted by cobalt327
I wouldn't remove the hard vacuum line to the modulator. Instead, cap one end and draw a vacuum on the other end. If the vacuum holds- and the line is clear- (no kinks or obstructions, check for this by blowing through it or pull a vacuum unplugged, it shouldn't hold), it's OK.

Some modulator lines went to a fitting on the intake that had a small orifice that acted as a sort of delay valve. If you still are using one like this, be sure the orifice isn't clogged up w/carbon, etc., or the tranny might shift weird.
I'll try that method then. I'll also check for the delay valve, thought I don't recall seeing anything of the sort.




Here are some close up shots of the spark plugs. The were wiped down after removal. I might have the order backwards (put away in a hurry), but they are the correct side.





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  #131 (permalink)  
Old 06-28-2012, 07:26 PM
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Those plug's condition look pretty bad, all in all. The photos are clear enough, but it's the electrode and ground strap and the porcelain that has the info; it helps to be able to see down inside the end of the plug- but in this case it's really not necessary.

I'd say considering how well the compression test went, that it may be the guides passing oil.

Is there one side of the plugs that is fouled more or has heavier deposits?

The one plug that looks most normal is the top right (circled).


Driver (L) 1-3; (R) 5-7


Passenger (L) 2-4; (R) 6-8
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  #132 (permalink)  
Old 06-28-2012, 07:57 PM
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Quote:
Originally Posted by cobalt327 View Post
Those plug's condition look pretty bad, all in all. The photos are clear enough, but it's the electrode and ground strap and the porcelain that has the info; it helps to be able to see down inside the end of the plug- but in this case it's really not necessary.
I was actually trying to get the camera to focus on the electrodes, but just didn't work out that way.




Quote:
Originally Posted by cobalt327 View Post
I'd say considering how well the compression test went, that it may be the guides passing oil.
I had to look up the procedure for replacing them. That's machine shop duty. Or will replacing the seals take care of this?




Quote:
Originally Posted by cobalt327 View Post
Is there one side of the plugs that is fouled more or has heavier deposits?
I'd say the passenger-side seems to have more fouling/deposits.




Quote:
Originally Posted by cobalt327 View Post
The one plug that looks most normal is the top right (circled).
Thank you for pointing that one out. Now I have something to compare against in the future.




I want to get an opinion: I am thinking of cleaning these plugs off thoroughly and using them one last time just to see where the oil/deposits end up. Or do they look just too far gone?
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  #133 (permalink)  
Old 06-28-2012, 10:40 PM
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Quote:
Originally Posted by lt1silverhawk View Post
I'd say the passenger-side seems to have more fouling/deposits.
In this case I'm talking about the individual plugs. Like we talked about earlier, where the idea was to try to tell if an exhaust or intake valve guide/seal was responsible for the oil getting into the chambers. An example (rather extreme, but shows what I mean) is:


It's obvious that the deposits are coming from whatever valve the encrusted side is facing. If the plug is marked for position, you will know if it was the exhaust or intake, although it's almost a moot point; at this juncture the only mechanical fix short of rebuilding the heads is to replace the valve stem seals to see if it helps.

I don't remember if you've used Seafoam or not but using Seafoam isn't just "pour it in and you're done". It can cause some crap to be on the plugs if the engine isn't "blown out" by some hard driving. There's a run down of how to go about it here, same place I found the plug photo.

Quote:
I want to get an opinion: I am thinking of cleaning these plugs off thoroughly and using them one last time just to see where the oil/deposits end up. Or do they look just too far gone?
You can go ahead and clean them off real good. I'd suggest using carb spray and a wire brush.

BTW, the gap looked to be wide on a few of them and a couple had the ground strap tilted up (worst one below); you'd want the gap to be around 0.040" w/the ground strap as close to parallel to the bottom of the plug as possible.



It's better to get the right plug gap from the get-go, than trying to bend the ground strap of a platinum plug IMHO. On some plug brands that means ordering up the right part number to get the gap needed. Anywhere from 0.035" to 0.040" will be OK.

If all the engine has seen is just idling in the driveway and putt-putting around the neighborhood, the plugs are going to look a lot worst than if you were driving normally, i.e. for an extended time at full operating temps at normal highway speeds.
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  #134 (permalink)  
Old 06-29-2012, 11:16 AM
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Quote:
Originally Posted by cobalt327 View Post
In this case I'm talking about the individual plugs. Like we talked about earlier, where the idea was to try to tell if an exhaust or intake valve guide/seal was responsible for the oil getting into the chambers. An example (rather extreme, but shows what I mean) is:


It's obvious that the deposits are coming from whatever valve the encrusted side is facing. If the plug is marked for position, you will know if it was the exhaust or intake, although it's almost a moot point; at this juncture the only mechanical fix short of rebuilding the heads is to replace the valve stem seals to see if it helps.
Got it. Going back to the previous post, you made it very clear that's what you were talking about but I missed it (been working long days ). The picture is a great example.


Quote:
Originally Posted by cobalt327 View Post
I don't remember if you've used Seafoam or not but using Seafoam isn't just "pour it in and you're done". It can cause some crap to be on the plugs if the engine isn't "blown out" by some hard driving. There's a run down of how to go about it here, same place I found the plug photo.
I did use Seafoam on the truck maybe once, but it was in the gas tank and not through the PCV or anything. Thank you for the link. I've never done it the way it is suggested on that thread, but I will follow that procedure in the future.

I actually just realized that I didn't know the proper way to pour Seafoam into a carbureted engine and looked it up. This seems like a good write -up: How to Seafoam your engine the right way. It says to use the brake booster line to the carb.


Apparently there is also a Seafoam Spray that can be sprayed directly into a carburetor throat: http://www.seafoamsales.com/how-to-use-sea-foam-spray.html




Quote:
Originally Posted by cobalt327 View Post
You can go ahead and clean them off real good. I'd suggest using carb spray and a wire brush.
Ok, I will do that and then inspect them once more.




Quote:
Originally Posted by cobalt327 View Post
BTW, the gap looked to be wide on a few of them and a couple had the ground strap tilted up (worst one below); you'd want the gap to be around 0.040" w/the ground strap as close to parallel to the bottom of the plug as possible.



It's better to get the right plug gap from the get-go, than trying to bend the ground strap of a platinum plug IMHO. On some plug brands that means ordering up the right part number to get the gap needed. Anywhere from 0.035" to 0.040" will be OK.
The gap I've been using has been 0.060" which seems to be the proper gap for a '77 California model. However, when I first did a tune two years ago, the original plugs were gapped at around 0.50" or 0.055", can't remember now. When buying new plugs, I will check to see what the gap is right out of the box. Should I stick with the CA gap?




Quote:
Originally Posted by cobalt327 View Post
If all the engine has seen is just idling in the driveway and putt-putting around the neighborhood, the plugs are going to look a lot worst than if you were driving normally, i.e. for an extended time at full operating temps at normal highway speeds.
Yep, that's pretty much all I've done with it for the most part for the last two years. Once everything is fixed, it will see more driving. I don't drive on the highway much anymore except on occasion, but I'll try to take it one the highway at least once or twice a week.
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  #135 (permalink)  
Old 07-01-2012, 04:54 PM
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Got to do some work on the valve stem seals.




I ordered a Powerbuilt valve spring compressor (presently going for $20 + free shipping on eBay) and a Lisle valve holder. The valve spring compressor is very similar in design to the units offered by Moroso, Summit, Jeg's and Probuilt but at a much cheaper price.







I popped off the passenger-side valve cover and found the source of the leak: a small piece of an older valve cover gasket. Can't believe I missed that. No more working at night. Lesson learned.







I hooked up the valve holder to the compressor. There were no directions included so I set it to 100 psi. I had a few moments of frustration because the valve spring compressor shaft that bolts onto the rocker stud was too big. The packaging said it was for both 3/8" and 7/16" studs. Turned out the the shaft has different threads on each end and has to switched. That required popping off a c-clip and reassembling it.







Once the compressor was correctly set up, I removed the retainer, spring and seal from the #2 cylinder exhaust (?) valve (the very first one on the right). Now, I need help identifying what I've got. Based on what I've seen and read so far, I believe these are the positive stop seals.


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