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| | | | Joined: Dec 2003 Posts: 2,953 'Bolter | | 'Bolter Joined: Dec 2003 Posts: 2,953 | When my 235 engine is cold, summer or winter, on initial start up I get very loud lifter/rocker clack. Almost embarrassing. About 10 minutes later its gone and you would never know it had happened. I have been using 10W30 oil with changes every 1000 miles. Someone suggested a heavier grade oil. The motor is a fairly new rebuild with about 10000 miles on it. Any ideas? | | | | | Joined: Oct 2001 Posts: 3,458 Extreme Gabster | | Extreme Gabster Joined: Oct 2001 Posts: 3,458 | This is a common problem on hydraulic lifter engines. What happens is that the oil in galleries in the engine drains back into the pan, and then the air is forced into the lifters when you start it up. Then they have to pump back up. Some engines have anti-drainback valves built into the oil filter, but a 235 wouldn't. I think there are some mods you can make to the lifters to help bleed off the air but I can't find the link I used to have.
Early Miatas were notorious for this problem. Sometimes a different brand or grade of oil helps, sometimes not. Its not really destructive per say, but it is embarassing. Adjusting the valve lash might actually help somewhat.
Last edited by 4ontheFloor; 11/28/2007 12:51 AM.
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A lone amateur built the Ark. A large group of professionals built the Titanic. | | | | | Joined: Feb 2001 Posts: 81 Shop Shark | | Shop Shark Joined: Feb 2001 Posts: 81 | I have a 62 1/2 ton Chevy truck with the 235 engine that had the same peoblem you described. The only solution I have found is to replace the lifters with solid ones and adjust them as solids. The engine is a little more noisy but no more leaking down. I did the same thing to an earlier 235 and ran it for many years and over 100,000 miles with no problems! Some readers will tell you you can't run solid lifters on hydralic cams but you can...
Green Machine
| | | | | Joined: Nov 2007 Posts: 29 Apprentice | | Apprentice Joined: Nov 2007 Posts: 29 | had that very problem with my 55 235 engine, tried rebuilt lifters, worked for a while and had the same problem. What finally fixed it, was I got a new set of lifters from Jim Carter's. They are hydrolic lifters, and 2 years later, no problems, no more knocking when you start cold. | | | | | Joined: Apr 2005 Posts: 1,971 'Bolter | | 'Bolter Joined: Apr 2005 Posts: 1,971 | If you are on a pacific island, run 30 weight. | | | | | Joined: Dec 2003 Posts: 2,953 'Bolter | | 'Bolter Joined: Dec 2003 Posts: 2,953 | The engine does have hydraulic lifters. | | | | | Joined: Apr 2005 Posts: 1,971 'Bolter | | 'Bolter Joined: Apr 2005 Posts: 1,971 | They don't seem to hold up when the oil is thinner. Try a 20w50 weight if you feel you need a multi grade.
| | | | | Joined: Jan 2009 Posts: 256 'Bolter | | 'Bolter Joined: Jan 2009 Posts: 256 | I know this thread is old, but I have the exact same problem. After sitting more than ~10 hours I have the cold start clank. It lasts until the engine is mostly warmed up. As far as I can tell its just a single lifter that is having problems pumping up. I'm using rotella t 15w-40. You are very right, its very embarresing listening to the engine clank away.
Should I attempt to replace the single lifter, or just accept a bit of clanking? | | |
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