Engine idles rough in "Drive" but fine in neutral or park...

[Twilight Fenrir]

I think I figured out why I cannot get a good seal on the drivers side of my exhaust... It looks like the pipes are contacting the frame and when I hit the gas the twisting of the engine puts pressure on them and opens up the joints. I will be investigating later today and hope to move things around a bit.

Is that with that exhaust setup you had linked to in the other thread?

[xgecko]

Yup. Not sure where the problem lies. It might be a bening issue that I would need to work out with Waldron's or, more likely, it has to do with how the muffler mounted. The hangers in my car did not make a great deal of sense so I did the best I could but I think I have the driver's side too high. If I can fix it by resolving this then it is clearly not due to a bending issue, but if not I will contact Waldron's to work it out. My experience with them strongly suggests they will work with me to get it right as they need to know for future customers; they clearly understand how important it is for the exhaust to be right while recognizing that it is something of an art. They are clearly dedicated to a quality product; in fact, they are in Centreville, MI and would love to have a Toronado in their shop to work with... Are you anywhere near there? If so, it might be worth looking into having them work with your car if you need exhaust; they have the capacity to take the car into the shop for fine tuning of the exhaust, all they need is a car.

I'll report back what I find once I get the muffler mounted better if I can.

[Twilight Fenrir]

And the results are in... not good

1: 168 2: 153
3: 15/90/15 4: 173
5: 150 6: 155
7: 155 8: 155


I cranked the starter for about 10 seconds per cyl, and wrote down the numbers. #3 I did a few times, hoping I had the tool mis-seated. After the first time, I became optimistic when it jumped from 15 to 90, I fiddled with it a bit more and it's back down to 15. It kept wiggling, but it never got up near the rest of the cyl's.

[69W34]

have you done both a dry then wet test and was the motor warm?

[Twilight Fenrir]

have you done both a dry then wet test and was the motor warm?

Dry and wet? And, yes, the engine was warm.

[69W34]

after the dry test the wet test is preformed by squirting oil (single or multi-grade) into each cylinder as it is being tested this (seals the rings) if nothing changes during the retest the problem in all likelihood is with the valves or upper end, if cylinder in question pumps up then there is a case to be made for bad, broken rings. The latter of course is not good news

[Twilight Fenrir]

Well, I took off my valve cover to have a look underneath, I figured I would hand-crank the engine and see if all the valves were moving. After going over the valve-train with a fine tooth comb, and reading every minute detail, I've determined the answer!

My rocker stud broke!

Which, also broke the little bridge-y thing that goes between the two valves on the #3 cyl. XGecko, do you still have your old Cyl heads? Any chance I could buy a couple of those bridge-y things?

The real question is going to be getting that broken bolt out... I know it should be cake for a machine shop, but is there any way I can safely perform the task? Or, if I have to bring it to a machine shop, can I drive the car there and have it done? Or do I need to pull the head for them to do it?

Thank god it happened on an intake valve.

[xgecko]

Egad. Yep, you sure do have a valve problem there. Hmm...

Here is a brand new Rocker Arm pair with the pivot on ebay:

http://cgi.ebay.com/ebaymotors/New-66-67-68-69-70-71-442-Hurst-Olds-400-455-Rocker-Arm-_W0QQcmdZViewItemQQhashZitem5ae1e3418aQQitemZ390336823690QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories



You should be able to extract the bolt by carefully drilling a smaller hole in the middle of the bolt - be sure to use a center punch or other tool to make a dimple for the drill to make sure it is in the dead center of the bolt. Then use a bolt extractor like one of these:

http://www.sears.com/shc/s/search_10153_12605?vName=Tools&keyword=bolt+extractor&viewItems=25&autoRedirect=true&prop17=bolt%20extractor

The good news here is that you know what the problem is and that it is reasonably easy to fix... Good thing the stock configuration is not an interference engine, eh?

[Twilight Fenrir]

Wow... okay, that was almost too easy... I think I need to take a hammer to it so I have more to fix >_> It started turning as soon as I took the drill bit to it.

Anywho, got the stud out, got my new pivot on order. Just waitin' for parts. Thanks

[Twilight Fenrir]

New pivot should be waiting for me when I get home, so tomorrow i'll replace all my rocker bolts with.my shiney new ones for good measure, and put in the new pivot.

On my El Camino, I had to turn the engine by hand to make sure the valves weren't open when torquing the rocker arms. Looking at how these ones are attatched though, it doesn't seem like I should have to worry. Is this correct? Can I just replace all the bolts willy-nilly, or do I nees to make sure the valves are closed when I do so?