SailNet Community banner

1 - 4 of 4 Posts

·
Registered
Joined
·
1 Posts
Discussion Starter #1
I have a 76 C-27 w/A4. Noticed this season when I start the engine I have several minutes where there is blue smoke in the exhaust (I assume from oil pooling in cylinders.) After about three to five minutes it seems to subside but will smoke a little at start up when coming in from a days worth of sailing. Also noticed this weekend where the lower 1/4 of the spark plug caps on the front three spark plug wires had melted a little. Been having some problems w/overheating but not to the extent that would cause this (temp runs about 180 and never exceeded 200.) Can anyone offer any suggestions? Am I looking at pulling the engine and an overhaul or is there a less expensive and/or less complex solution?

Lysle
 

·
Registered
Joined
·
62 Posts
If oil consumption is very little, don''t worry about it....Some other reasons for the smoke is....old or clogged oil filter, old or overheated oil(oil at high temps breaks down & becomes thin. when engine is at running temp, pull dip stick, if dripping off alot change oil use Rottella 15w-40)Change your spark plug wires and get a cooler thermostat installed..Again, if not using to much oil don''t worry...but change filter, oil And stat to let it run alittle cooler....
 

·
Registered
Joined
·
5,067 Posts
Do NOT use Rotella (diesel grade) oil in your engine!! Use standard HD oil used in gasoline engines.
Check the water output at operating rpm, just collect the ouput in a bucket .... it should be 3 gallons per minute, if less check for a blockage: piece of impeller that migrated in the cooling loop, salt fouled block (raw water cooled), large pieces of rust (platelets) inside the exhaust manifold - all easily fixed.
If raw (salt or brackish) water cooled, the correct thermostat is 145 degrees. If fresh water cooled, 180 degrees. DO NOT run this engine without a thermostat installed ... as it is a bypass thermostat system. With the thermostat removed the cooling water will entirely bypass the engine block. .....
There are many situations (most minor) that will cause an A4 to smoke a little. Most can be solved by removing the old crankcase oil, replacing with Marvel Mystery Oil, running till warm WITH NO LOAD with the engine (in neutral), then shut down, put a few tablespoons full down the (cleaned) sparkplug holes, crank with the starter with the spark cable to the coil off/removed so that the engine cannot start ... and let sit a week or more. Will clear a lot of carbon fouling of the piston rings, etc. If the piston oil control, etc. rings are stuck with carbon debris, the engine will smoke, etc.; the MMO will help to clear the build-up (and you might even notice better compression!!!). Then drain the MMO, replace with regular oil (good to use 1/4 MMO + 3/4 regular oil in the crankcase)

If you need additional help ... join the Atomic-4 eMail discussion group on the Sailnet message boards. Don Moyer sells a comprehensive (best one ever written) Maintenance and Repair Manual for the Atomic-4 @ www.moyermarine.com ...
good luck. Hope this helps.
 
1 - 4 of 4 Posts
Top