New crate 454
Last month I broke the crank in my 1988 Winnebago Super Chief. It had only 57,000 miles on it. I located a GM crate engine 454. I took my time and installed the engine piece by piece. I went with a n...
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We are on our third 454 in our RV. Neither of the two replacements ran hot from the crate. The first (factory original) lasted a long time, the second (bored out with thinner cylinder sidewalls) only 30,000 miles and blew out one side of a cylinder shortly after it began to overheat. We chased several things to solve the overheating - rebuilt the radiator, bought a new high performance radiator, replaced the fan and clutch. It turned out that the hydraulic fan clutch caused the original problem and the replacement clutch we had installed was bad. It would seem to clutch correctly if you spun the fan blades relative to the clutch for one or two turns, then suddenly the clutch would disengage completely and stop driving the fan.
I could literally grab hold of the fan blades with the engine running and stop the fan even though the engine was way into the red overheat region. After engine 2 blew up, we reinstalled the "new" fan clutch - still saw overheating - and we also heard that the overheating was just due to tight tolerances in the crate motor (#3). Fortunately, my expert adviser said that was baloney and we kept tracking it down until the fan clutch was identified as the source of the problem.
I'd doubt that it's just something caused by the crate motor that will go away by ignoring it. Triple check that d!@#$%^n fan clutch and if it's not that, follow up on the other leads in this thread.
I could literally grab hold of the fan blades with the engine running and stop the fan even though the engine was way into the red overheat region. After engine 2 blew up, we reinstalled the "new" fan clutch - still saw overheating - and we also heard that the overheating was just due to tight tolerances in the crate motor (#3). Fortunately, my expert adviser said that was baloney and we kept tracking it down until the fan clutch was identified as the source of the problem.
I'd doubt that it's just something caused by the crate motor that will go away by ignoring it. Triple check that d!@#$%^n fan clutch and if it's not that, follow up on the other leads in this thread.
