#1
IP: 67.182.135.54
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Funny A4 story..and valve job question
Greetings,
I have had my Columbia 29, 1965 since 1989 and still love it. My A4 now has a compression pattern of: 105 psi 38 102 30 If I put oil in each cylinder and repeat the results are not much changed. I conclude that the valves are bad or not seating well in two cylinders. My plan is to remove the head and valves and inspect closely. How does one grind the seats in an A4? Are there special tools required? My funniest A4 story is when I sucked up water in very rough seas a few years back and flooded the engine with saltwater. I removed the plugs and cranked a lot then added oil drops. By this time my battery was too low to crank it over fast enough to restart it. My solution was to install just ONE spark plug.....I then got it actually running with three plugs out....and kept adding plugs to get back to four. I swear it's true. Keep it mind for when your battery is low and you don't have a hand crank. Dave |
#2
IP: 68.109.228.113
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A few things to check
Dave,
I'm no expert, but I have had simular issues. It is either the valves of head gasket. Check the plug condition upon removal. They can tell you a story. Are the wet or dry? You should be able to see all the valves without removing the head. The ones forward of the spark plugs are diffucult, but you should be able to shine a light. I can't help you with the valve info. Sorry That is a good story and makes sense. That is what is great about the A4. It always wants to run! Chief |
#3
IP: 67.182.135.54
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Cheif,
I put on a new head a year ago.....since the low cylinders are not adjacent I think it is the valves. I have pulled the side cover and "pinged" them closed to make sure the springs are ok and the valves have some gap clearance. I am going to pull the head....just wondering about how one "faces" the valve seats. I want to get all valves ground or replaced and do the seats. Since the other 2 cylinders have 100 psi I think the rings are OK and I don't want to pull the whole engine. Thanks for your feedback. Dave |
#4
IP: 76.237.200.76
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Valve Lapping
The standard procedure for doing valves on old flathead engines was to remove the cylinder head, disconnect them and then "lap" them with grinding compound. For disconnecting them, a spring compression tool was used, being careful not to drop any of the keepers into the oil pan. You would use "coarse" compound, then use "fine" compound. A suction cup on a stick was used, and some engines had two shallow holes on the valves for a special tool to lap the valves. A soft pencil was used to draw several lines vertically on the lapped surfaces and then give them a slight rotation. If all the lines were partially erased, you were good. Any old timers recall this procedure?
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