Here's my final plan... With Some Questions

Well I decided to take the advice of many of you and rebuild the 454 crusaders in my 1985 32ft FB. The main reason is that I can salvage my season. The rebuilding job at a well known speed shop in my area, who also does work for many boat dealers in the are, has told me it will take two weeks and about 3k per engine. They will do it all from top to bottom end. I was going to just have them machine the block and top end but I think if I let the do the entire job that'll give me time to "restore" the engine compartments and other items while the engines are out. My plan is to use these engines for the remaining part of this season, next season and then maybe after using them for about two years pull them and upgrade to the Cummins 330 diesels. The timing just isn't right for me financially to upgrade at this point. I have a lot of other things going on.

Now for the questions...I'll list them for ease..

1) The rebuilder says he has 454 parts that are better than the quality of replacement original crusader parts. He thinks they'll last longer and hold up better to the distress a marine engine is subjected to. What are your thoughts on this? Should I insist on OEM?

2) With the engine mounts...I will be using the same ones but the bolts that go into the stringers are heavily corroded. If I can get them out can I simply replace them in the same holes or must I epoxy them and redrill? Wasn't sure if they'd hold in the original hole that was used.

3) I was wondering what your thoughts on "phasing in" my diesel conversion would be? I was thinking that maybe during the next time I have her on the hard I could upgrade the through hulls for the raw water intake and the exhaust for the upcoming diesels and a few other items? Will a bigger exhaust (from 4 to the 6in required for cummins 330) be too much of a drop in exhaust back pressure for the 454s?

4) While the engines are out I will be replacing the manifolds. The engines are FWC and I was wondering if I should get the manifolds that are original to the engine (risers are positioned to the back end of the block) or are there any benefits to using the newer style where the risers are positioned towards the middle of the block. If I change manifols style I will not be able to use the elbows and risers I just replaced, but I was wondering about the benefits of changing the style.

5) Can I upgrade to 1.75inch shafts during the next off season and still use the 454's? (I want to get as much of the conversion done while I have the boat out during the off seasons so that I can basically just drop the cummins in place.)

Sorry about the length of this and of course....thanks for all your comments in advance!

Jack

1. He's right, of course, but the question is, does it matter? There are better pistons, rods, cranks, valves, rings, lifters, oil pumps, bolts,...virtually every part of the engine. I wouldn't bother. preparation/machining of the block is THE critical part of engine preparation.


2 Unless the holes are elongated or enlarged because the originals were loose, or there's some structural problem with the area around the mounting points, replacing the bolts will be fine.

3. It sounds as though you are "By-God-determined" to have diesels. I frankly see no point in a boat this size - the gas engines will serve at least as well; probably better with all things considered. Regarding the phased approach with the exhaust... I do not recommend this. The increased exhaust tubing size will reduce low/mid range power. This has to do with engine exhaust wave resonance, not "backpressure" but it will occur. As a general rule, Large exhaust tube diameter increases top end power at the expense of low end. The reverse is also true. given a choice, between the two, low/mid range is much more useful unless it is a racing engine

4. I don't know which is better...Unless there is a known problem with the old style, I would use them. Crusader manifolds/risers/elbows are considered to be a better design than many other marine engines. For some good info on risers in general, see: www.yachtsurvey.com/exhaust_risers.htm

5. Sure - changing the shaft size is not an issue for the engines. You will, of course have to change the appropriate couplers to attach the shaft to the tranny.

6 No, don't convert this boat to diesels! (I know, you didn't ask this question) :)
And also take a look at this page: www.yachtsurvey.com/GasDiesel.htm

Good Luck

MikeP

Mike,

Thanks for the quick respone. (Guess I am quick in responding as well. Don't feel like working all that much today. Have more important things on my mind...like the boat).

I decided to take this route for dealing with my current power issue because it gives me time to sit back and think further about diesels as well. Yeah...I'd love to have a set in my boat. I do quite a bit of offshore fishing myself, run some charters and cruises from here to there and would really benefit by the repower because of milage. I have previously read the articles you posted. Very thorough. Gas engines with this boat won't allow me to goto the canyons without a large amount of aux. Fuel. At 0.5mpg my current fuel capacity won't allow it.

So Tuesday I plan on beginning to get the engines out of the boat and hopefully by Thursday will have the engines to the rebuilder.

I'd be cautious with converting major items (i.e. expensive) items over to diesel requirements before you've ready to buy the new engines. Make the plans, but save your pennies. You never know how things are going to change in the next few years. If you spend $2,000 on upgrades, then decide to sell her, where would it have gotten you? Not many buyers are going to recognize that it has bigger shafts, or larger exhaust ports. Those items will only be appealing to someone set on going to diesel as well.

Most of the conversion items you've mentioned can easily be done over the off-season around here. Then, by the spring, all you'll have to do is drop in the engines.

Just my $0.02.

Fred

His response is sound. I would add one comment on parts selection. Speed shops like to beef up cams - it's their nature - they can't help themselves. Be sure that the original spec marine cams are used, or you will likely round off lobes in short order, and lose a substantial amount of power.

With regard to the motor mount lag boltss, I'm not sure if you have removed them yet or not. If you have, great. You can always drill out the hole and epoxy in a good hardwood dowel, then redrill and lag in the original location. I would not just fill with epoxy.

If you have not yet removed the lags, there is a chance you may snap one or two in the process. I snapped three out of 16 when I did the 327's in my old Chris about 8 years ago. Rather than damage the stringers more by digging them out, I had 1/2" steel plates 3" x 5" fabricated. I drilled 2 holes in them - one to line up with the motor mount hole, and one offset behind the motor mount by about an inch. The hole that lined up with the motor mount lag hole was tapped for a fine thread 1/2" bolt. I inserted a bolt + lockwasher thru the motor mount and bolted the plate to the underside of the mount. Before reinstalling the engines, I mortised out a 1/2" x 3" x 5" section of the stringer for the plate to set flush (my stringers were 3" wide - adjust accordingly). Be sure to align the threaded hole with the original lag when mortising for the plate. This is critical to engine alignment. I was then able to lag thru the second hole in the plate to attach the engine to the stringer. Good luck with the project.

Bob

i think you made right choice. however i would strongly recommend you replace the distributors with electronic ignition type. we rebuilt the mallory distributors and added the pertronix ingntor. Mallory did the rebuild for about 60/ distrubutor and the ignitors were 63 each,purchased over internet from dealer in ca. however i have been told the the Prestolite distributor is better. also you may want to have someone rebuild the quadrajets. these 2 items can greatly improve economy.


i am on my way today to our boat in stuart fl to complete the distributor installation. dont have floscan to measure economy difference but all the data indicates we should see a difference.


if you want info on any of my recommendions, please feel free to call me over weekend on my cell. or e mail me directly.

steve hierholzer
4079285173
shierh@aol.com

Good point on the pertronix. I installed them in my 327's rather than swap out the entire distributors, as I have mechanical tach drives, and they made a world of a difference. Great bang for the buck.

Not necessarily in order....
1) I would not upgrade the Crusader manifolds/risers. They are fine as they are. They work well, and you won't get the additional money back when/if you sell them.
2) Leave the exhausts alone as noted above. What if you do decide to get a different boat? You won't get the exhaust upgrade $$$ back either.
3) Making the through-hulls bigger is a good idea. It doesn't cost a lot. The only catch is this: when you repower, they aren't going to be in the same place. You'll have to move them anyway. So...I would replace your old sea valves because they are probably due for it, or recondition them, but if you make them bigger (and you would have to go to 2" for Cummins B diesels) you can count on having to move them anyway. They aren't going to be in the same place, trust me.
4) Better ignition upgrade- MSD marine distributor and MSD-6 ignition box. Costs more, though.
5) You didn't mention what carburetors you have, but IF you have Quadrajets, you might consider upgrading to Edelbrocks, which are a one-piece Carter design made by Weber and sold by Jeg's or Summit Performance. I did this on my old 454s and they performed quite a bit better and used less fuel. They are easy to tune and all the metering changes can be done from up above with a kit that comes with the carburetor. Or used to. They are not a spreadbore like the QJet, they are a Holley pattern.
6) I would change as LITTLE as possible and save your money for the next go round. And leave your shafts the way they are. If you want the shaft, pull up at the fuel dock when your boat is back in the water. Gas or diesel, they'll slip it to you right now.