Sticking valves, lubrication etc. |
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CJ2AH
Member Joined: 13 Mar. 2023 Location: Sweden Status: Offline Points: 4 |
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Posted: 13 Mar. 2023 at 5:15am |
Hi,
new to this forum. Own a -46 CJ2A with the original L-head engine. Restored it back in 2000. Since then it´s been used very occasionally during summertime. Past year it has been really hard to start, and eventually it did not fire up at all. Was expecting carburetor or ignition issue, however finally found that I had some valves that had stuck open. After some effort of repeated tapping them down/cranking them up, they are now loose. Are sticking valves a common issue on these engines? Anything I can do to prevent it from happening again? I must admit that I have not changed oil as should during the years after restoration. Could that be a root cause? Another question about lubrication. From where are the valves and their guides lubricated? Only relies on splash oil from somewhere? When cranking the engine with valve cover off I cannot see any lubrication. However might need higher speed to build up oil pressure enough? Thanks a lot for input. BR Johan
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CJ2AH
Member Joined: 13 Mar. 2023 Location: Sweden Status: Offline Points: 4 |
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And a picture of the engine itself. |
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Oldpappy
Member Joined: 09 Apr. 2018 Location: Tennessee Status: Offline Points: 4812 |
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Sticking valves is not uncommon when an engine sits for long periods without being started. One of the secondary oil galleries provides lubrication to the cam, tappets and valves. When the engine is running the oil is under pressure will spray into the valve chamber from the base of the tappet bosses. The tappets, and valve stems should get plenty of oil while the engine is running, but when it sits for long periods this oil will drain off due to gravity. Looks like you pulled the head to unstick the valves. This is not necessary. Stuck valves can usually be freed by these steps. 1) Disconnect the coil wire so the engine will not start, and remove the spark plugs. 2) Rotate the engine manually with a wrench on the crankshaft nut until the tappet for the stuck valve is all the way down. 3) Insert a feeler gage or knife blade between tappet and valve and rotate the engine to push up on the valve. Spray some penetrating oil onto the valve stem, and a little into the spark plug hole for that cylinder while doing this. Note: The feeler gage or knife blade should be thicker than the adjusted lash so that the valve will be pushed further up than when the engine was running, but not thick enough to cause too much lift. Tony Norton wrote a very good article on the L134 lubrication system. The article was the topic of the below thread on the G503 forum, and is something you may benefit from.
Edited by Oldpappy - 13 Mar. 2023 at 8:17am |
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If you can't get there in a Jeep you don't need to be there!
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Tom in RI
Member Joined: 07 May 2009 Location: RI Status: Offline Points: 1124 |
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Johan,
Glad you are on a path to get the jeep back on the road. The best way to keep it running is to drive it. And when you do drive it put more than 50km on before putting it back in the garage. When you take longer drives, the CJ can heat and burn off internal condensation. You will get lots of opinions on how often to change the oil. I live near the coast so everything rusts fast here and moisture is everywhere, even in the garage. So I try to change oil once a year if driven less than 1000mi on the jeep. Sometimes it may be 2 years..but I try. |
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tamnalan
Member Joined: 08 Oct. 2013 Location: Port Orford, OR Status: Offline Points: 986 |
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I made the mistake of trying to burn up some old gas a couple of years ago at the Fall Color Tour. A valve promptly stuck, and bad.
My advice: if you smell any "varnish" odor in your gas tank.... drain the fuel and use it for something else. Combusting it in your motor may gum up your valves like it did for me. I would ask about valve guide clearance, but your motor looks well run... it's probably varnish like it was for me. Joe Friday had the good idea of running a spray solvent .. brake cleaner, I think .. down the carb in a running motor. Sure enough! The valves freed right up, but the smoke was horrible. I really trashed poor Mike's shop when we did that. Try that trick, OUTDOORS.
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Alan Johnson
1942 MB - "TBD" 1943 MB - "Lt Bob" 1950 cj3a M-100 x2 teardrop camper: https://forums.g503.com/viewtopic.php?f=141&t=201740 |
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tamnalan
Member Joined: 08 Oct. 2013 Location: Port Orford, OR Status: Offline Points: 986 |
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Cool front fenders on your jeep, Johan! Welcome to the 2a forum! Great people and advice here.
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Alan Johnson
1942 MB - "TBD" 1943 MB - "Lt Bob" 1950 cj3a M-100 x2 teardrop camper: https://forums.g503.com/viewtopic.php?f=141&t=201740 |
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CJ2AH
Member Joined: 13 Mar. 2023 Location: Sweden Status: Offline Points: 4 |
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Thank you all for help. Certainly seems I found the right place to ask questions
Will keep you posted about the progress. When the Jeep first came to Sweden in the -40´s it was rebuilt with a cab and water pump to act as a firetruck. Probably it got the front fenders at that time as well. In the 70´s my grandfather bought and used it as a multi-purpose vehicle for our farm. I planned to restore it to original fenders during restoration, but given it´s history and the fact that it looked kinda cool I kept them as they where. Another unusual thing is that the serial plates are stamped CJ2AH. Can´t find anything about the "H" online but I think it´s for Heavy duty or High load simply because it has one extra leaf spring on each suspension. Edited by CJ2AH - 15 Mar. 2023 at 8:57am |
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muley
Member Joined: 25 Jan. 2021 Location: idaho Status: Offline Points: 816 |
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I dig the exhaust stack and cab in the early foto!
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Joined Jan-8 2015
I never met a mule I didn't like! OD Mule 01-52 M38 Big Red 19fiddy CJ3A salad |
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