Merc 420 Cyclone engines

[BDC1013]

You are going to want to take drives off and send them to some competent dealer. They require special tools and not everybody can work on them. Even if you don't send them out you'll want to take them off to change fluid grease and inspect cross bearings. Plus it is very difficult to install engines with drives on.

Rear mount is nice to have but very difficult to fabricate mounts to stringers and align properly with assembled engines. That is typically done with a dummy block bolted to trannie assembly. For the sake of not overburdening yourself just leave it for now. You can always attend to it in the future.

Steering is typically on stb engine. The inside transom plate will dictate that.

Flywheels are not interchangeable. you must use flywheel that came with the engines. Ring gears can be moved in many cases. Flex plates are inter changeable. The bigger the springs the better. The 540 likely had a heavier duty flexplate. Hardin sells HD flex plates at a reasonable price.

Back to drives. I believe it is very important to know they are good. Few internal parts are available. Fewer used assemblies are available. If your drives are beyond repair it changes the entire job.
Hopefully the fluid is clean and no moisture is present. They must hold lube. if the lube is creamy drain and refill and send out. Never drain lube and leave empty. ESPECIALLY is water is present.

Best of luck. I'll check in when I can.

I'm currently searching for a place local to me that I can bring the drives to. I know everything has been sitting for such a long time it would be a shame to grenade a nice set of classic drives. I have a feeling they are ok but I'd like to have them looked at to confirm. At minimum I think all new seals for the drives and some cleaning up with fresh paint would be nice. Also where do you get new gaskets for mounting against the transom? Is there tricks to sealing all this up?

 

[BDC1013]

 

[BDC1013]

Fuel system is next up. Boat has 4 fuel tanks. I've found (2) belly tanks under the floor 125 gal ea. and (1) 80 Gal. tank under the rear seat. Last tank seems to be in the front of the boat somewhere. Havent got to it yet. The two belly tanks have some varnish. Should these tanks come out or can i clean them with some kind of chemical? I took the 80 Gal tank out because it needed to come out to get to the two belly tanks. I'm almost thinking maybe ill just use these three tanks and forget about the front tank, but not sure yet.

 

[Bobcat]

Some solid Gas Tanks!

There's gotta be Someone Local to do those Drives....Cali is the Birth of all things Hot Rod!

Glad to see this thread back!

 

[BDC1013]

Some solid Gas Tanks!

There's gotta be Someone Local to do those Drives....Cali is the Birth of all things Hot Rod!

Glad to see this thread back!

She holds some fuel that is for sure. 4 tanks, haven't even bothered with the front tank yet. 330 Gal with utilizing just the 3 rear tanks I feel should feed me for some time? I'm lucky if I get a gal per mile im told?

I'm trying to find someone local, I just got the drives off the gimbles and they are on a pallet.

I'm very happy to be back, this project has been a life goal. Finally at a place in my life where it was time! Glad to see some familiar user names already replying to me!!

 

[BDC1013]

 

[BDC1013]

Questions!!

Lovett 1200 bilge pumps still available? 1 powers up and 1 is dead. I dislike how high these sit in the the boat, as there would need to be a significant amount of water in the bilge for them even to suck anything. Was thinking of changing to a different style that I could put a pickup hose on to aim it lower to suck from the low point of the bilge.

What can you tell me about the props? 15x24 is the size and P22 is the pitch? LOL and ROD are which sides they go on?

After draining the fuel tanks, what should I pour in there to eat of the varnish? I have two empty 55 gal fuel drums and fuel pump to suck out the fuel.

Tailpipes... Boat had inner and outer flappers. Is it necessary to have both or is one or the other sufficient? Do these change the sound or muffle at all?

Where can I get the hydraulic rams for the drives or do I just have them rebuilt? Have one missing and also would like to replace bushings.

When draining the drives they both had about the same amount of fluid in them, quite a bit actually. My guess would be somewhere between 12-15Qts. Only a little water came out first out the bottom not much when draining. They both spin freely and easily, hopefully everything check out good. Still trying to find someone to open them up, check, repair if needed and reseal/paint.

Transmission velvet drive oil cooler. The velvet drive pumps its own oil through the cooler or do i need some external pump? I've read GM Mercon III for fluid?

Thanks Gents!

 

[fund razor]

Pumps: When I did mine I went with new Rule pumps. They move a lot of freaking water. Remember that you can have a lower water pickup, and also have lower float switches. Mine go on before there is very much in the bilge total. When I have put water in the bilge to test them, one discharges each side, and they look like a fire boat in a parade. Another thought is make sure they are wired, switched, and fused independently, with both auto and manual capability. Then you will be all set.

ETA: flappers. I have dry exhaust and one flapper on the outside of the pipes, which stick out about six inches and have a pretty mean angle to the elbow with the boat in the water. Whether you should change your setup would depend on your confidence in keeping reversion down. (See dry exhaust... lol)

Usually trim rams are repaired before replaced, when possible.

I will now get out of Jim's way for the hard stuff.

 

[BDC1013]

Pumps: When I did mine I went with new Rule pumps. They move a lot of freaking water. Remember that you can have a lower water pickup, and also have lower float switches. Mine go on before there is very much in the bilge total. When I have put water in the bilge to test them, one discharges each side, and they look like a fire boat in a parade. Another thought is make sure they are wired, switched, and fused independently, with both auto and manual capability. Then you will be all set.

ETA: flappers. I have dry exhaust and one flapper on the outside of the pipes, which stick out about six inches and have a pretty mean angle to the elbow with the boat in the water. Whether you should change your setup would depend on your confidence in keeping reversion down. (See dry exhaust... lol)

Usually trim rams are repaired before replaced, when possible.

I will now get out of Jim's way for the hard stuff.

Ive been looking at all the different style bilge pumps. Where the old Lovett 1200's were mounted was on a platform about 3 inches above the bottom of the bilge. I would imagine there would have to be about 3-5 gallons of water in the back before they even started sucking anything. To me, I want a tube that little sucks the water off the lowest point in the bottom of the bilge. I dont want to have be shoving 10 beach towels down there to soak of all the water to dry it out.

Tournament L/W Pump 1100 GPH "FC" I found this and was thinking of making a mount and running a pickup hose to the bottom. BUT this are not auto bilge pumps and the boat is wired to have auto on/off as well as switched activation.

My exhaust is wet. I was thinking if the boat had both style flappers i should probably just stick with that, as there's probably a reason. I just don't trust the rigging on this boat, seems like there was a lot of cocaine being done while this was being assembled in Florida in 1989 haha

Yeah i need to find where i can take these rams to get rebuilt but i still need 1 and also the bushings for mounting them.

 

[BDC1013]

Need some guidance here. My guy out here on the west coast has informed me of the bad news of the first drive he opened up. Water was in there and the prop shaft is rusted and pitted where the seal goes. Also the gears in the upper half have some rust pitting as well. He said i could get away with replacing the prop shaft and be ok for a little while with the uppers. He also said the nose cone is seized onto the drive and hasnt been able to get it off yet. Should i be looking for parts? A whole new drive? I searched ebay and there is some stuff on there. I figured there might be a subborn crusty ol bastard on here hoarding all the #3 parts so id write a post! Should I start a new thread in driveline tech? Thanks gents.

 

[Ratickle]

Stubborn crusty ol bastard? :rofl:

 

[Ratickle]

I'm starting to dig into possibilities....

 

[MOBILEMERCMAN]

Its a shame you got a mess on your hands. There are a few different generations of #3's. I'm not sure who to say which is which. There are different prop shafts for sure. Different spline counts. If it were only the shaft issue you may be able to overcome with speedy sleeves. Pitted gears are another story. Using pitted gears is a loosing deal. Chances are good is gears are pitted bearings are too. Bearings can be purchased buy the numbers on the bearings and cups. You need to get them apart and be able to read the numbers. If the housing wont come apart there isn't much hope.

Be careful what you buy on e bay. I think you'd be lucky to buy anything worthy.

I too have drives that are way out of production with few parts new. I spent the last 10 years collecting spare parts. AT some point all parts will be gone. AT that time Bravos will be the go to. It involves filling transom and re drilling, re rig engines and mounts. It will cost as much or more then boat is worth just to make it useable.

 

[Ratickle]

I think try to talk to Mel Riggs at Mr. Marine in Fond du Lac Wisconsin. He used to buy out all of Mercury's discontinued products.

Another would be Mike at CK Motorsports in Nunica Michigan. He may have some #3 parts.

Let me know if either can help. If not, I'll keep thinking.

 

[BDC1013]

Update: Drives

Okay, after a bit of down time working on the boat I'm back at it. The prop shafts have been saved, I sent them over to a friend's machine shop to have them "reworked". We are not sure how this will turn out but I think everything will be fine. I found Don at High Power Marine to go through the drives for me. He is local out of Discovery Bay, CA. Don was very nice to work with and he was able to tear down both drives, inspect, pressure test and reseal/lube them all up. I have since blasted them and will be painting them shortly. Also was able to purchase a new old stock sticker pack that was submerged in oil and completely useless other than to be used to recreate. Not sure if this is legal or not so I'll leave who i used out of this haha!

 

[BDC1013]

We got one of the engines in the boat: Need to figure out what to do with the exhaust and lining the tail pipes up to exit the transom. They are off quite a bit. Suggestions?

 

[MOBILEMERCMAN]

Congrats on getting our drives in order.
Exhaust tailpieces come many different ways. I can't say for sure what you have other then bravo tails. Some have more rise and extra bends like yours. Mine are more of a straight shot.
You are either going to need different tailpieces, cut and reconfigure, or change where the go out and fill what holes in transom you have. You could have custom pipes made. That will be pretty expensive.
Its been a long time but there is a way to measure. Maybe you can search and find a build sheet for Gil custom tailpieces. A good place to start is take a tail piece off, lay a straight edge on the flat top of manifold where 4 studs are and extend to existing transom holes.

 

[MOBILEMERCMAN]

 

[MOBILEMERCMAN]

https://www.cpperformance.com/instructions/420-901180i.pdf

This is a start.

 

[MOBILEMERCMAN]

Look in my project thread here on this forum. Fountain/ Lucky and Perfect . Post 198 and 199 shows pix of my exhaust. I suspect you need something similar to what I have.