Repower

Post by **dougl33** » Mon Jan 10, 2005 10:56 am

OK, A fellow on another site gave me a link: http://tcmarineengines.com/default2.html It looks like the longblock 7.4 without tranny, manifolds, risers, or carb is as follows: L - 31.47 inches W - 23.16 inches H - 25.9 inches The 8.2 longblock has the exact length and width. It is slightly taller at 26.33 inches. Considering that there's a 33 FBC on Yachtworld that has got the F.I. 8.2's. I'd be very surprised if the 8.1's didn't fit. Regards, Doug L. 1986 33 Bertram FBC Queen Elizabeth

billb · Post by **billb** » Tue Jan 11, 2005 2:43 am

Tim and Doug: there is two styles of "big blocks" 502's.. one is the regular low deck block and the other is a high deck or tall block.....the tall or high deck block 502 you probably will have clearance problems.....just get the low deck or regular block motors...does that make sense????does that help at all??? Bill Beeson RAZZMATAZZ

photo finish · Post by **photo finish** » Tue Jan 11, 2005 6:08 am

why did the 8.1 496 replace the 8.2 502 ? Tim Stamm Photo Finish 1981 33' Bertram FBC

Post by **dougl33** » Tue Jan 11, 2005 7:43 am

Tim, Its more of a replacement for both the 7.4 and the 8.2. They probably replaced them because GM is no longer using either motor in their cars or trucks. Regards, Doug L. 1986 33 Bertram FBC Queen Elizabeth

billb · Post by **billb** » Tue Jan 11, 2005 7:58 am

Tim: The 8.1 engine and the 502 are different motors completely....the 8.1 is the new vortec style engine with tune-port injection...in other words an injector for each cylinder and is computer controlled..the 502 is a direct replacement for the old 454...comes carburated or throttle body injection.....does that make sense???I still dont think you would have any clearence issues on either one.....the 8.1 is the latest and greatest big block engine, but it has a lot of sensors,and all computer controlled...just dont know how it will be in the marine environment....that should totally confuse you.....let us know!!!! Bill Beeson

photo finish · Post by **photo finish** » Tue Jan 11, 2005 8:05 am

I talked to crusader today directly.the 8.1 is 2" taller than the 454 and the heat exchanger is on the rear which is the highest part of the merc 454 which is on the front of the engine.The engine does not sit totally flat it still angles down a little at 4 degrees coupled with the 8 degree down angle tranny puts it at what the 454 sits which should be 12 degrees. i did not know that the crusader manifold is still cast iron while he said mercs being alluminum is not tried and true.Thoughts? he said without a dought do the 385 not the 420hp and that the fuel cooler on the crusader cools better. also for you computer geeks you can buy the software that reads and evaluates the ECM for $579....cool Tim Stamm Photo Finish 1981 33' Bertram FBC

photo finish · Post by **photo finish** » Tue Jan 11, 2005 8:21 am

thanks Bill...i would assume that the performance would be equal between the 8.1 and 8.2 however i would bet the fuel economy on the 8.1 would be much better.the longevity of the ecm and the sensors in the salt and heat is always a concern. Tim Stamm Photo Finish 1981 33' Bertram FBC

Post by **dougl33** » Tue Jan 11, 2005 10:10 am

I don't know about anyone else, but my heat exchangers are on the rear of the engines. I'm not sure which year they changed it. My engines are 1986. I'm still having a hard time believing that 2 inches in height would make a difference between them fitting or not. Regards, Doug L. 1986 33 Bertram FBC Queen Elizabeth

captgene · Post by **captgene** » Tue Jan 11, 2005 10:19 am

Yeah, my Heat Exchangers are on the rear of the engine too. But tell you what..from the top of my flame arresters to the floor I only have about 2 inches clearence. I'm going to look in my papers. I should have the installation drawings for the 7.4 to see where they are measureing from. This is turning into a group project with Tim doing the funding. E.W. Dugan

will newton · Post by **will newton** » Tue Jan 11, 2005 11:49 am

This is great stuff! Y'all could start your own repower consulting firm. Unfortunatly, I sold my boat (before doing what Tim is doing) but I can't stay away from this site. Tim, the Crusader people I have spoken with here in Jacksonville, Fl (they have a dist office here) sell to a lot of MerCruiser marinas. Lambs Yacht Center here in Jax became a Crusader dealer some years ago and they sell and service both Merc and Crusader with no problem. Call Crusader and tell them they need a full service marina in your area NOW. I can't believe a marina operator who is a full service outfit would not bend over backwards to get the Crusader dealership. There has to be a full service marina down there near you who will do the Crusader dearlership...it is not that big of a deal to become one!! You need to lean on Crusader to make it happen...maybe they will make a project out of you to get a dealership started. Good luck. I'll leave it to you pros. Thanks for letting me drop in. Now I go back to my pitiful outboard world....... best, Will Newton Jax Fl

lobsta1 · Post by **lobsta1** » Tue Jan 11, 2005 3:12 pm

Just came across this link: http://www.marinepowerusa.com/eng%20specs/8.1v.htm Has some good spec drawings. Al 1978 33 FBC NITES OFF

photo finish · Post by **photo finish** » Tue Jan 11, 2005 3:22 pm

Will, I bet you never thought your post would go this far....The problem with crusader in my town is that the premiere dealer/installer is not on the water and he thinks he can trailer my boat with a half tower to his shop and keep it there for 8 weeks.i have had 3 shops say they will trailer it and i just laugh. Tim Stamm Photo Finish 1981 33' Bertram FBC

Post by **dougl33** » Tue Jan 11, 2005 3:33 pm

Tim, What is your objection to having the boat trailored? Just make sure you find out how much there going to charge you. If they can find a way to get to their shop that doesn't include going under over-passes then I'd let them do it. Regards, Doug L. 1986 33 Bertram FBC Queen Elizabeth

photo finish · Post by **photo finish** » Tue Jan 11, 2005 3:38 pm

thanks al, crusaderengines.com has the same measurements as well that is where i am measuring. if you take 22" above the crankshaft and measure down 6"to where the tranny meets the shaft thats 28"...i really think that if there is an issue it will be the oil pan hitting the cross stringer and if that is the case then the combination of longer shafts moving the engines back and forth it will fit with no modification. still no marina wants my money yet i am still waiting. Tim Stamm Photo Finish 1981 33' Bertram FBC

franklyprice · Post by **franklyprice** » Tue Jan 11, 2005 4:22 pm

Tim, Do you suppose that the reason it's difficult to get anyone interested in a re-power is because evryone's busy with hurricane repairs? It seems that normally a decent re-power would be a great job for a marina.Weird. Also trailering your boat from the Naples area would be tough, wouldn't it? From what I understand the area is built up enough that there must be all kinds of wires and bridges and such? Frank Price