Huge mistake!!!

T

Thomas Molin

New Member
Jun 15, 2008
50
Gothenburg, Sweden
Boat Info
330 DA, 1997
Engines
2x454 Mercruisers V-Drives
Have spent about 200 hours last month every night after work and every weekend to rebuild my 330 DA completely.
Bought and installed 2 remanufactured 7,4 which I was supposed to start up yesterday and splash the boat today.

Realized that my starboard engine wouldn´t get into gear and read the manual of the Hurth V-Drive. Now!!! I realized that the Hurth drive can not work with an engine with reversed rotation which is exactly what I have bought...:smt013

I guess the only thing to do is to pull out the engine again and either change the drives or dismount the engine and change the camshaft, oilpump etc to change rotation of the engine?

First time I have done any work with engines and at least I have learned a lot!!! For example that it is much more cheap to hire a mechanic compared to try to do it yourself;-) Or maybe that it could be a better way to check what you need before you buy it... Hope to get splashed before the summer is over anyway.:smt021
 
WOW... And I thought I had problems rebuilding my Westerbeke... I hope you enjoy working on the boat... It is half the fun... sometimes...
 
Mistakes is how we learn. That sounds like an expensive and time consuming lesson to me. Sorry to hear about your trouble.
 
Wow... sorry to hear this.... dumb question, but is there any chance you can return the engine and swap for the correct one?

A while back, I had a similar issue with a pair of rebuilt 4.3s. I decided to upgrade HP from 175 to 205 only to find out that the splines on the driveshaft were different. The rebulder took the engines back and sent me the right ones. I was out a few hundred in shipping, that's all...

Best of luck with your "issue" as well as the boat, when you get'er done!
 
Can't you run that trans in reverse? - if you do need to "convert" the motor don't forget to change the rear main seal too as I believe they are directional
 
Thanks guys for your support and wishes. I bought the engines from a guy who had imported them to Sweden from US. His boat was caught by a fire before he had them installed so there are no possibility to change them since I didn´t buy them from a dealer.

Anyway, what I have found out is that the V-drive is fully reversible and can run the shaft either way from a standard rotating engine. The cheapest way appears to pull the engine and change direction. For me as a totally beginner in that area it seems like a huge project, but a friend of mine who is a car mechanic and has worked with chevys for decades, calmed me down and promised to help with the work. 4 hours to pull the engine and pull out the cam and try to figure out where it comes from.

A little googling to find the factory in US that can sell me the same cam with the other rotation. A week to ship it to Sweden and another half day to put the engine together again and install it in the boat. And voila! The boat hits the water!

The total cost for the parts would be around 1000 USD so it´s actually quite cheap compared to buy new drives. I´m just mad about myself for buying stuff before I check out what I need...
The biggest issue at the moment is that summer finally came to town this week after an extraordinary cold and long winter and my boat is not even in the water yet;-)

I´ll keep you updated and will get back with some pictures of my modifications.
 
Wasn't there another post on here with a similar question? Someone mentioned that just swapping the cam would not allow the engine to rotate in reverse. They also mentioned that the pistons must be swapped/changed as well? Double check that.

Doug
 
You will most likely need to swap out your starter drive as it will be reverse rotation. I was visiting a good friend in Sweden and we were the Boltic Ocean last year. Great pictures at 11:00 in the evening.
 
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Yes, that is correct. I also have to change the starter and oil pump and some other stuff as well, but it is still much more cheap and easier than change the drive.
Glad you liked to boat in Sweden OldSkool even though you just have seen the backside of our country that way;-) You should try the west coast next time.
 
Thomas Molin said:
Yes, that is correct. I also have to change the starter and oil pump and some other stuff as well, but it is still much more cheap and easier than change the drive.
Glad you liked to boat in Sweden OldSkool even though you just have seen the backside of our country that way;-) You should try the west coast next time.
Click to expand...

You cannot change the direction of the motor without a complete teardown. The pistons are indexed toward the rear in a counter rotating engine. This is because all modern engines have a slightly offset wristpin to counteract the torque the weight of the piston imparts on the thrust side of the bore. If the pin was in the exact center the bore would wear in an egg-shaped pattern. If this is not done I would guess you would wear out in a hurry.
 
ShamuToo said:
You cannot change the direction of the motor without a complete teardown. The pistons are indexed toward the rear in a counter rotating engine. This is because all modern engines have a slightly offset wristpin to counteract the torque the weight of the piston imparts on the thrust side of the bore. If the pin was in the exact center the bore would wear in an egg-shaped pattern. If this is not done I would guess you would wear out in a hurry.
Click to expand...

Thanks! I will show your post to my mech to see if that makes any sense to him. I will post further information about how it turns out. The last weeks I have not had any time to think about boats because of to much work.
 
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