Thread:

1971 kona w/berkley jet 455 olds

just getting into vintage speed boats and i got this kona and can't find any info out there for it. who made it ? where? are there any resources? I blew the engine up easter weekend, so of course its already @ the machine shop. Of course I'm ppumping it up alittle more. where can i find info on this boat or something similar? HELP!

Stop right where you're at. Call the machine shop and tell them to throw that motor out and start looking for a Chevy. No, I'm not kidding. Since you're just getting into this, there is no reason to go backwards. This is boating, and depreciates fast enough without having to dump more money into that Olds. Trust me, I know. I went through 2 motors in 4 years. I had #3 still running when I sold the motor. My first one blew the first week I had it. My wife did the same thing you did. (Assuming) Hold it to the floor for more than 15 seconds, suck the oil pan dry, start welding the bearings together at 4800rpm and knock knock knock. You can build it faster, quicker and throw all the money at it you want, but its not going to fix it. Although, its the beginning of the season, and if that motor is truly close to being finished...run it. Don't abuse it, and start doing some homework on why Olds are hard to expect longevity in a jetboat. The HB site was loaded with great Olds threads, but we're new over here and don't have the archives built up yet. Yes, there are Olds guys out there, Maxwedge, Travis Hathaway, and maybe one more...
I was one of those guys, and have never looked back.
Good luck.

PS: What were the circumstances when your motor blew? What went?
I fused #7 and #8 bearings in one motor, snapped a crank in another.

Good Advice! [quote=Wet Dream;110483]Stop right where you're at. Call the machine shop and tell them to throw that motor out and start looking for a Chevy.

I agree Matt, There's no real reason to replace the motor if the motor can be rebuilt. Oiling has been the main issue with the Olds motors and that can be fixed. Depending on what you really intend to do with the boat, I'd go back the way it was, with a little over build and have fun. Summer is coming and a boat sitting in the driveway due to motor issues is going to suck!

There are a lot Olds out there living and breathing just fine on the water. If later on you want to get radical then you can do that on the side and be ready to make the change all at one time. Think about this, to swap out to another motor right now, you will need the motor, the headers, the mounting rails, just to name a few. Headers, new, $1000.00, mounting rails or stringer mounts, upwards to $500.00, motor, who knows what it'll need, and then some wiring changes. Not to mention a new drive line and the list can grow from there.

Want more power later on, then build on a stand and gather the parts as you find the deals. Get ready for summer now and have fun.

Originally Posted by GAWnCA

I agree Matt, There's no real reason to replace the motor if the motor can be rebuilt. Oiling has been the main issue with the Olds motors and that can be fixed. Depending on what you really intend to do with the boat, I'd go back the way it was, with a little over build and have fun. Summer is coming and a boat sitting in the driveway due to motor issues is going to suck!

There are a lot Olds out there living and breathing just fine on the water. If later on you want to get radical then you can do that on the side and be ready to make the change all at one time. Think about this, to swap out to another motor right now, you will need the motor, the headers, the mounting rails, just to name a few. Headers, new, $1000.00, mounting rails or stringer mounts, upwards to $500.00, motor, who knows what it'll need, and then some wiring changes. Not to mention a new drive line and the list can grow from there.

Want more power later on, then build on a stand and gather the parts as you find the deals. Get ready for summer now and have fun.

You know as well as I do that you WAYYYYYY overpriced that stuff. Try looking for some used ones. Motor, $500, Headers $200, Rail kit, $250, Stringer kit $75-100. If money isn't a hurdle, then neither is a Chevy. Those 2 things you mentioned and priced cover ONE machining. Then you have to address all the oil issues and do this and mod that and when THAT motor blows, you'll be afraid to take it over an idle. Then you're into ANOTHER motor. By now, you could have had a nice mill for what you have into the Olds.

Originally Posted by matt1840

i think a safe number to play with to completly switch over to a chevy would be close to 4500 possibly more. Depending on what condition the chevy motor is in when you take it to the machine shop. Think of atleast 3000 in parts and labor at the machine shop to build a reliable chevy, and the additional parts to get it runnin. If youve got the cash make the change go with the chevy, if you wanna be on the water this summer.... run the olds.

Who said anything about taking the motor to the shop for any kind of machine work? Thats right, you did. You can pick up used race motors or mild runners cheap. Hang on, I'll be back with a quote from you, and some numbers.

Originally Posted by matt1840

Have the machine shop "race prep" your block. Enlarging, deburring, and polishing all your oil passages INCLUDING the heads and lifter galley, and be sure to match the head gaskets to the passages. Purchase the correct oil restricters from an olds performance parts manfacturer NOT MONDELLO!! Be sure to run the correct clearances for a "race application" for the pistons ring to cylinder clearance, considering boat motors are at a higher rpm when compared to a car engine,Fully balance the motor and use arp studs on the bottom end, rods and heads and you should be fine. My current setup includes

olds 455 fully race prepped fully studded
keith black forged 10:1 pistons
slight port job on fully rebuild Ka heads (want edelbrocks)
comp cams Xe274 camshaft .230/.236 duration @.50 .520/.523 lift
king race berrings
and both heads have had the rear tapped for direct oil return to the pan
offenhauser tunnel ram 2 edelbrock 750 carbs (lookin for holley 450's)
mallory ignition system
bassett Ot headers
mondello 10 qt pan and pump

This motor should last me quite a while, im not out smashing the gas all day long either. I just wanted a nice jetboat to cruise with the occasional foot to the floor. The build was going to originally cost me $1500 But with having to source a new block, crank and rods it jumped to much more.

Maybe its just me, but that sure seems like a shit load of money for a "jetboat to cruise with". How much do you have into the machine work and hardware? What heads are you running? What rockers?

Thats just me talkin, i have never bought an engine and just thrown it into somethin. Every motor i get my hands on i always take it to a machine shop and have it gone over. 1 for reliablility reasons, and 2 so i dont have any interesting suprises ruin my fun. And id like to know where i can purchase a "race motor" for less than $3000... Doesnt matter if its a fresh motor, or one thats been ran, show me a reliable race runner that is under $3k.

Originally Posted by matt1840

Thats just me talkin, i have never bought an engine and just thrown it into somethin. Every motor i get my hands on i always take it to a machine shop and have it gone over. 1 for reliablility reasons, and 2 so i dont have any interesting suprises ruin my fun. And id like to know where i can purchase a "race motor" for less than $3000... Doesnt matter if its a fresh motor, or one thats been ran, show me a reliable race runner that is under $3k.

You should get to know some of the local track drivers. They are a hell of a source. You know, dirt, circle, oval racers. Not Nascar.

Matt, what heads are you running?