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Chris Craft 431 Identification

MVY

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I just purchased a CC Constellation with 431 engines. When reading about these engines, I notice several designations after 431. Some I have seen are are H, HR25 and A. What do they designate? Do they indicate different variations of the engine, and if so do they take different parts, gaskets, etc.? Where can I get a repair manual for this engine? I have an owners manual which gives little information.
Thanks
Mark
 
Based on a 430 CI Lincoln car engine. Chris Craft marinized this engine, it was their first big displacement engine to be used where their 327 (210 hp )Chevy wasn't big enough. They were rated at 275 HP @4000 rpm.Chris Craft made an earlier version called a model 430, same horsepower as the 431. The 431 had
had many improvements over the model 430. This engine was unique to Lincoln cars (and maybe optional in some Mercury's and Thunderbird's).
Lincoln made these engines in about 385 CI (?) 430 CI and 462 CI. Chris craft only used the 430 CI engine.
These engines are not related to 352,390,427,428 FE Ford engines. Also not related to later 429 and 460 Ford engines. I don't think the 430 CI engine was ever used in trucks or any heavy duty applications.While they are a nice smooth running engine they don't take well to being run hard. I would cruise them at about 2800 rpm if that is a good speed for the hull. Synthetic oil should be helpful. Mobil 1 15-50.
Chris Craft replaced these engines with model 427 (300 HP) which was based on the high performance 427 CI FE series engines.
The reverse gear was a large Paragon Gear made in Taunton,Ma. I believe Twin Disc bought out Paragon.
I recall the distributors were Mallory Flat top (YL) models with dual points. Convert to electronic ignition.
Finally the HR25 might be Hydraulic (reverse gear) Right hand rotation and 2.5 to 1 reduction. Check to
see if the other engine is marked HL25. I don't recall if they had self adjusting hydraulic lifters or solid lifters that had to be adjusted periodically. The car version would have hydraulic lifters. I assume your boat is about 40' + -
 
Yes, it is 45 ft. Everything original. Engines about 1600 hrs. Very well maintained. I have located and purchased complete spare engine sets from a similar boat being stripped for salvage. I plan to switch all lube to synthetic. Don't know why anyone would run their motors over 2800 rpm except in emergency. I see valve lash info in the manual - will check that. Seem like high torque/lower speed motors. Understand the 430 used a generator and the 431 an alternator. The distributors have already been converted to pertronix. My engines are Stbd: 431HR & Port: 431-HRO25 The spare set use the same prefex. I also got a motor out of a speedboat and it is an 431H (no gear reduction). Perhaps the "R" is reduction and the "O" is opposite rotation? Thank you for the reply with great information! Mark
 
The 430 is an MEL engine... that is, Mercury Edsel Lincoln division of Ford Motor company. It was introduced in 1958, and with a marauder tripower option, was the first production V8 to hit 400 horsepower. It was raced by Ford in 1958 and 1959 in Tbirds, and almost won the first Daytona 500 in a Tbird driven by Johnny Beauchamp. It is rumoured that the first Bertram to win the Miami to Nassau race in 1960 was powered with 430's. The 430 was offered as a powerplant in many of the Chris Craft cruiser line to over 50 feet. The first 430's, as stated, were generators, and had a single double impeller waterpump from Sherwood. The later 431 had two pumps, the second one for circulating. The large journals on the mains and rod bearings tended to generate more heat, and CC had some cooling issues in the early version in the larger boats. There are other differences between the motors, including intake runner size, piston design and compression, and some minor head changes. While a low rpm engine, the 430 has a very flat torque curve from 2000 to 4000 and produces immense torque figures at low rpm. The HR25 refers to the hydraulic reverse and 2.5 to 1 reduction gear. Marine gaskets are no longer made for the 430, and neither are north American oversize bearings. You can get Chinese replacements. Dave Van Ness at Van Ness engineering in New Jersey has rebuilt a few of these engines, and has the hard to find gaskets. There are a big list of subtleties in the 430 that would slip by a lot of engine builders. They are a very tough engine, and properly applied and cooled are hard to kill. The big issue is cost of rebuild. The combustion chamber is in the cylinder, not in the head, and the deck is surface 10 degrees to the bore, like a 409 Chevrolet.


The 431 and 430 used solid lifters. The valve lash is .025 hot, and .027 cold. You wont find the stepped pistons anymore if you rebuild, unless you order custom forgings.

I have a 1965 21 foot Superport that came with a 430 originally. If you want a significant database of info on these engines... go here ford-MEL-engine.com. I post there under Chris Craft Crazy.
 
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Yes, it is 45 ft. Everything original. Engines about 1600 hrs. Very well maintained. I have located and purchased complete spare engine sets from a similar boat being stripped for salvage. I plan to switch all lube to synthetic. Don't know why anyone would run their motors over 2800 rpm except in emergency. I see valve lash info in the manual - will check that. Seem like high torque/lower speed motors. Understand the 430 used a generator and the 431 an alternator. The distributors have already been converted to pertronix. My engines are Stbd: 431HR & Port: 431-HRO25 The spare set use the same prefex. I also got a motor out of a speedboat and it is an 431H (no gear reduction). Perhaps the "R" is reduction and the "O" is opposite rotation? Thank you for the reply with great information! Mark
Hello Mark, Sounds as though you have acquired a "boat load" of engines as well as knowledge on these motors. I am new to them after acquiring a 1965 CC Commander 38' last year. I am still on a learning curve. I have replaced all hoses and lots of cleaning. While removing the 3-1/4" exhaust hoses that connect to the wye pipe the elbow from the riser broke off. After further inspection I found one other one was also very tender. I was hoping you might have a set you would be willing to "liberate" so I can get my girl off her skids. Or maybe you have a source. Thanks and I hope your enjoying your Chris Craft.
 
Sorry about your breakage! My engines do not have that exhaust set up. Mine have a large stainless steel muffler crosswise over the transmission. Pipes welded to it are bolted to the exhaust manifolds. A third pipe exits to the rubber exhaust hose clamp, then on to the copper pipe carrying it to the stern.

Hello Mark, Sounds as though you have acquired a "boat load" of engines as well as knowledge on these motors. I am new to them after acquiring a 1965 CC Commander 38' last year. I am still on a learning curve. I have replaced all hoses and lots of cleaning. While removing the 3-1/4" exhaust hoses that connect to the wye pipe the elbow from the riser broke off. After further inspection I found one other one was also very tender. I was hoping you might have a set you would be willing to "liberate" so I can get my girl off her skids. Or maybe you have a source. Thanks and I hope your enjoying your Chris Craft.
 
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