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Old 06-29-2012, 10:16 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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