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New Member with Questions
https://www.slantsix.org/forum/viewtopic.php?t=15629		 Page 1 of 1
Author:  Guest [ Wed Jan 04, 2006 11:50 am ]
Post subject:  New Member with Questions
Hey, I'm new here as I just aquired a 1963 Valiant convertible with a 170 /6 and 106,000 miles. I tried all new tune up stuff and oil conditioner, etc. for sticky valves and/or rings to no avail. It sat unrun for 3 years and now runs rough with low compression in cylinder 2 and 5. Cylinder 5 also has a bent pushrod. I have antifreeze spewing out of the rear drivers side valve cover bolt (when removed). Is this normal? I'm thinking I have a cracked head, bad head gasket, and/or bad valves. I'm going to do a final compression check tonight. If I squirt oil in the cylinders and the low compression ones don't change, the head has to come off. If the compression comes up I guess I have to pull the whole engine. Any thoughts?
Author:  dusty7t4 [ Wed Jan 04, 2006 12:11 pm ]
Post subject:  Re: New Member with Questions
Quote:
It sat unrun for 3 years and now runs rough with low compression in cylinder 2 and 5. Cylinder 5 also has a bent pushrod. I have antifreeze spewing out of the rear drivers side valve cover bolt (when removed). Is this normal?
no.

you got somthing big wrong in there.

have you pulled the valve cover completely off yet? it does sound like the head could be bad (cracked) but for freeze to be coming out, you lost closure on a waterjacket someplace

-dave
Author:  Slant6Ram [ Wed Jan 04, 2006 5:41 pm ]
Post subject:  Pull the head
This sounds like something which could be fixed by removing the head and replacing with a rebuilt unit. It's common for a couple of valves to get stuck when a motor sits for a long time.

The antifreeze leak doesn't sound good, but are you sure you are removing the valve cover bolt and finding a leak? There are several other bolts which will allow leaks if removed,(normally) but I've never seen antifreeze leak out of any of the holes of the 7/16 valve cover retaining bolt holes.(that would be bad)

If the leak isn't being caused by a cracked head, then you might be able to loosen up the stuck valves by spraying some penetrating oil under the valve seals and then tapping the rocker arm on top of the valve gently with a small hammer (to work the oil in) until free movement returns. I've had 100% results with this method on about 4 old heads. It's worth a try. Really badly stuck valves may require removing the manifolds and spraying oil on the lower part of the valve stem (though the port) while tapping. :wink:
Author:  Reed [ Wed Jan 04, 2006 7:03 pm ]
Post subject: 
Hi and hello there! I concurr with the above diagnosis. It sounds like you have a cracked head. THis is actually okay since the 68+ heads are "better" anyway. I say go to a boneyard, grab the cylinder head form a 72-80 slant six and sap it on. This will give you the "revised" combustion chamber as well as the ability to run unleaded gas.

If you have the time, money,mand knowhow, I would also grab the electronic ignition system, dual field alternator system, camshaft, and lifter from the donor car. Swap all that in with a new timing chain and you will realize a world of difference.
Author:  Guest [ Thu Jan 05, 2006 5:32 am ]
Post subject: 
Thanks for welcoming me and for the replies. I did another compression test last night with erroneous results. I pulled the valve cover off and now I have 3 bent pushrods, all intakes, that I probably caused by slugging the high idle running engine with Marvel Mystery oil through the carb. But the response to the 7/16 valve cover bolt spewing antifreeze tells me the head has to come off. I agree that I should locate a modern head with hardened valve seats for unleaded fuel.

I know the 225 /6 has a one inch taller deck height. Are the pushrods different between the 170 and 225, or are they all the same length?
Author:  mcnoople [ Thu Jan 05, 2006 5:54 am ]
Post subject: 
The pushrods are different 170 to 225. 1 possibility is stuck compression rings for your low compression. But you still have to deal with the coolant issue. Push down on the valves by hand if you want to know if they are stuck. I wouldn't expect intake valve pushrods to bend unless you really dumped in the marvel mystery and hydrolocked it and if you did you would know it. I would say siezed valves and the pushrods were the sacrificial part that bent first.
Author:  Guest [ Mon Jan 09, 2006 6:31 am ]
Post subject: 
Eureka!. 3 valves were stuck. I tapped the valve stems with a hammer after spraying copious amounts of WD40 on the valves and springs. I replaced the bent pushrods, put those Autolite 985 plugs in, and it started and ran pretty good. As far as that weird problem with the valve cover bolt spraying antifreeze when removed, I just put thread sealer on it and put it back. Now I've got some drivability issues with the BBS carb (I think). I ordered a rebuild kit.

Thanks again for all your help.
Author:  sick6 [ Mon Jan 09, 2006 6:37 pm ]
Post subject: 
you don't have any antifreeze in the oil do you? as in when you pull the dipstick its got sort of a white foam to it? that might let you know a little more.

I'd hate to see you just put the bolt back in without finding where its coming from.
Author:  VDART [ Mon Jan 09, 2006 6:48 pm ]
Post subject: 
--car is running better -- good-- now before you spend $$$ on machine work----- re adjust the valves--
most likely they are in dire need of adjustment--- .010 on the intake side & .020 on the exhaust for starters-- some guys have custom numbers -- but this is factory spec. adjust them at normal operating temp-- low idle speed-- you'll get the hang of it.

Now retime your car---- if your plugs/wires/points are good -- spray bomb your carb (clean it on the car) check that it is tight on the gaskets & try to adjust for a smooth idle-- then drive your car -- pay attention to how it sounds-- & change fluids if anything doesn't look smell right.

point is--- do some tuning --adjustments before machine work big dollars are spent-- the slants are tough motors & a little storage time just adds to it's character.

also do some searching on this site you'll find interesting problems & solutions that will help you

Keep us updated & you'll be cruising right along!!!!
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