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Counter rotating Crusader 350

willow

Regular Contributor
Been away guys...wife with a medical issue..(resolved)..anyhow, I see my port Crusader, (1991) 350CID seized during the winter.

Found out when we went to start it a few days ago. The engine has been pulled and I guess I have two options.

(A) rebuild..or
(B) purchase a new 350 CID Chevy small block and mount all the gizmos on it

The problem is......if I can't find a 350 ready-built with a counter rotating crankshaft, is it a big deal to take the old crank out, (assuming it is OK), and switch it in a "normal" rotating 350CID ??

Comments???

Don Keye
 
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It not the crank that differs between the two rotations but the cam, its drive, and the starter/flywheel interface.

Another option is to buy a reman'ed long block and swap your bolt on pieces to it. Many come with warranties at reasonable prices - check the T&Cs before your commit.
 
So a LH and RH rotation both use the same crank. I would only have to install the flywheel and starter from the old engine to the new and also install a new cam and drive(for a LH rotation engine) is that correct??
 
Hey Don, Very nice to see you back...Hope things are turning better for your spouse...Sorry to hear about the engine too...AL
 
Not quite that simple.

The cranks are the same...just spin in opposite directions - means correct starter and mating ring gear (on the circumference of the flywheel), with the bevels matching the starter's drive.

The CAMs need to be selected as RH or LH. Their drive will usually differ - chain on LH and gears on a RH. The cam (either rotation) will behave as a LH device. This lets the same distributor get used.

The last thing that usually needs to be done is to fix the pistons' thrust faces' orientation. In essense, you need to turn them on their pins 180 degrees. Not all pistons have a preference (designated thrust face) but good + quality ones do.

of course the raw water pump will need to be reconfigured for the opposite rotation.

I think that's the detailed list; sure somebody will ID any hole left.
 
Been away guys...wife with a medical issue..(resolved)..anyhow,
I see my port Crusader, (1991) 350CID seized during the winter.

Comments???

Don Keye
Don, your Port engine should be LH rotation, correct? The Starboard engine should be your RH rotation (reverse rotation) engine....Yes/No?
Should be easy to find!
Or is this particular Crusader installation different?

There have been several recents threads regarding RH rotation engines lately.
Due to oil pump rotation, all of these distributors should rotate standard.... however, the driven gear is changed!
I just changed a RH rotation to a LH rotation for a man earlier this week.
 
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Hi Rick,

Yup, it is the Port engine which is a LH rotation (I have V-drives)) Good old Crusader even has a yellow sticker at the back of the engine showing a LH rotation.

Makomark.....can I not just use the starter and flywheel from my "seized engine" ie: swap out the parts??

I was not aware of the piston switch.....is that a mandatory item if I buy a RH longblock and want to change it to a LH rotation??

Can I not just swap the raw water pump as well??

(as you can see...I have never rebuilt an engine:eek:)

Thanks for all the help guys.....it is a holiday up here on Monday so Tuesday we either rebuild or buy a long block:rolleyes:
 
Hey Don, Very nice to see you back...Hope things are turning better for your spouse...Sorry to hear about the engine too...AL


Hi Al,

Yeh it has been a weird winter. Short notice and the Admiral was on the table getting her Mitrol valve repaired in Toronto. Also had the Maze procedure done....stops erratic heartbeat. (She had been experiencing atrial fibrillation and then a "leak" in the Mitrol valve was discovered in November) That all happened in the last couple of days in March.

Her recovery has been excellent and the hardest thing is trying to get her to take it easy...sorta like trying to tatoo a soap bubble !!

We planned on getting "wet" on 01 June but when we went to proof out the engines we found the problem....my mechanic says we may make it but I'm not so optimistic...but such is life.

All the best...any day on the top of the grass is a good day !!:D
 
The engines use the same raw water pump, the only thing that changes is the inlet and discharge hoses are reversed.
 
Don:

As long as your old stuff is serviceable AND compatible with the new piece, reuse is always an option. Didn't mean to say you had to buy new; only that you need to have the proper 'flavor' of those parts.

Those yellow arrows Crusader uses indicate shaft rotation which isn't always the same as the engine rotation. This is were the particular gear used comes into play. Some can do full power reversing, some can't (at least not for long). Check the serial number plate on the engine for its designation.

The LH rotation assemblies are much easier to find than RH ones....usually cheaper, too.

As far as the pistons go, if they have a designated thrust face, I'd change them, especially while the engine was out of the hull. Nothing worse than putting it all back together only to have to repeat the process (& spend the extra money). A good machinist can usually get them back to you the same day as long as you coordinate your visit with there schedule. Of course, one could always invest in some piston tools and a press.

Glad to hear CINC-HOUSE is almost 100%.
 
Don:


Those yellow arrows Crusader uses indicate shaft rotation which isn't always the same as the engine rotation. This is were the particular gear used comes into play. Some can do full power reversing, some can't (at least not for long). Check the serial number plate on the engine for its designation.

The LH rotation assemblies are much easier to find than RH ones....usually cheaper, too.

As far as the pistons go, if they have a designated thrust face, I'd change them, especially while the engine was out of the hull. Nothing worse than putting it all back together only to have to repeat the process (& spend the extra money). A good machinist can usually get them back to you the same day as long as you coordinate your visit with there schedule. Of course, one could always invest in some piston tools and a press.

Mark.. Ok..I'll check the serial number plate.....will it confirm LH or RH rotation? I assumed on a twin, with V-drives the Port engine has to be a LH rotation...yes ?? Am I wrong in assuming the yellow decal with the arrow on the back of the engine pointing in an anticlockwise direction is not indicating a LH rotation??

What exactly are you referring to when you state LH "rotation assembly"? Are you saying a LH rotating engine??

PS...I'll pass on the piston tools and press..thanks:D
 
Don, I'm wondering if there is some confusion here regarding LH -vs- RH rotation!
Are you perhaps confused on this by chance?
LH is standard! RH is reverse rotation!

Marine engine rotation is determined as if viewing from the flywheel end.
All standard rotation engines are LH rotation..... in other words, they will turn Counter Clockwise when viewed from AFT.
This is considered standard and is the same rotation as automobiles and trucks.
Port side marine engines are typically Standard Rotation..... (Counter Clockwise if viewed from AFT.)

Starboard engines are typically the RH engines..... (Clockwise Rotation when viewed from AFT.)
These are the ones that need to be built differently... including front/rear main seals!

See post # 3 here.
 
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Ahhhhh..the light dawns !!!! So the Port engine is pretty near a standard engine whereas I thought a LH rotation engine was the "odd one". Thank you for the link as well.

Well that is certainly nice to finally and absolutely know !!. There is a marina close at hand that has three rebuilt 350s for sale and would it be wrong to assume that if they came out of single engine boats they would all be LH rotation???

It is all starting to become clearer..thanks for your time and Info.;)
 
Don, you are very welcome!

I tried to tell you this in post # 6.... and I was reluctant to repeat myself until I read further. Seemed like no one was catching this Stbd/Port...... RH/LH thing.
I then decided that I'd speak a little bit louder.... glad I did! :)

This should make it a little bit less expensive for you too!
Good luck, and if you enjoy a project like this, have fun doing it!

.
 
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Ok...now here is what I think is correct. (Crusader 350CID):rolleyes:

Bear in mind this is the PORT engine and I have V-Drives.(so engine is in the boat backwards)

1) one views the direction of engine rotation from the rear

2) My engine has a "rotation arrow" that states it rotates in an anticlockwise rotation so it is a LH rotation

3) I now run to the front of the engine and it appears to be rotating clockwise, as does the drive shaft that goes into the V-Drive.

4) The V-drive then changes the prop shaft rotation and the prop shaft is now turning to the LEFT, (Counterclockwise)

5) to make sure, I look at the(PORT) left hand prop and it has a big "L" at the hub.

Ergo, I must have removed a STANDARD small block Chevy 350 (LH rotation) and finding a replacement should not be a big issue. Is it safe to assume that the flywheel on the STANDARD (LH Rotation) engine I find is a non issue and that all the gizmos from my old engine should be easy to just swap to the new longblock??

(Ps...... I had to draw a multitude of sketches to get this to sink in but I think I have it now)

I know marine engine knowledge is not rocket science but for me it is all new....ask me about a jet engine and I could go on for years !!!:D

Finally.....my Crusader manual shows a LH rotation engine with this firing order .....

1-8-4-3-6-5-7-2

Any comments or observations would be appreciated...tomorrow we decide what route to go....buy....or rebuild.
 
Don, that firing order is correct for a Standard Left Hand rotation engine...... whether Marine or Automobile.


350_firing_order.gif


A Reverse, or Right Hand rotation firing order, will be reverse of the above!

The LH/RH firing orders will mirror one another when we consider # 1 to be the first cylinder firing.

Successive cylinders to fire in standard LH direction > 1 -8-4-3-5-6-7-2

Successive cylinders to fire in reverse RH direction > 1 -2-7-5-6-3-4-8

Or another way to mirror it:
1-8-4-3-5-6-7-2-----2-7-5-6-3-4-8-1

.
 
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Thanks to all for helping me out...I'll post more results as the week progresses and maybe, just maybe, we will get "in" on schedule..... 01 June:):)
 
Don, more food for thought here:

It was't until post #7 that you mentioned "V" Drives.
However, you do not mention which V drive!
Part of what you may want to know, is that there are two/three ways in which a V Drive can work.

**Some use two gears, which means that the V drive reverses the engine rotation out to the propeller shaft. Engine rotates one direction/drive rotates prop shaft in the opposite direction.

**Some use three gears, which means that the drive corrects counter rotation, and the prop shaft turns same direction of the engine even when considering that the engine installs Flywheel End FWD.

**Some are reversing capable..... which means that either engine can be Standard rotation..... i.e., LH.... and the prop shafts can be made to counter one another!
Port prop LH
Stdb prop RH

So, you'll need to determine a few more things.

I know that this engine is locked up so you can't use the starter motor to help you. So one very easy method would be to find # 1 plug wire on the distributor cap.



In a Standard CW direction at the cap, see which cylinder fires immediately after # 1.
If #8 is next, then you have a Standard Rotation engine.... LH
If #2 is next, then you have a Counter Rotation engine.... RH

That should help you determine which rotation engine you have to replace.:)
.
 
**Some use two gears, which means that the V drive reverses the engine rotation out to the propeller shaft. Engine rotates one direction/drive rotates prop shaft in the opposite direction.

.

Thanks for the info....;)

My V-Drives reverse the direction of the engine drive shaft rotation. My V-Drives are ..

Crusadervdrive.jpg


Crusader V drive Transmisssion Model 4500

I had to replace one two years ago and had the the old one fully repaired so now have a spare V-Drive...if you know of anyone who needs one...this totally refurbished V-Drive might be for sale !!!:rolleyes:

In this case the engine is rotating counter clockwise as viewed from the back of the engine...which is installed on the port side of the boat and has the front of the engine facing the "wake".

This means, when viewed from the front of the engine that the driveshaft is rotating clockwise into the V-Drive.

The 2 gear V-drive reverses the direction of the propeller shaft and causes the prop to rotate counterclockwise as viewed from the back of the boat. The prop has the letters LH on the hub and the pitch of the props is such that the prop has to rotate counterclockwise, (LH), to produce forward motion of the boat.

I purchased a chevy 350 long block today......we have to remove the oil pan that came with it as the dip stick is on the RH side and when the engine is installed (front facing stern), the dipstick will not be accessible as it will be very close to the port side fuel tank. We will swap the old oil pan for the new and all will be right with the world.......oh yeh, had to buy an electric fuel pump as they no longer make mechanical fuel pumps for the 350s.

It is now time to install the tranny and all the other gizmos from the old engine....... more later.:)
 
Don, I believe that you are correct IF your V Drive uses only two (2) gears for FWD!
IOW's, if you turn the main shaft one direction, the prop shaft will turn in the opposite while in FWD gear.

If that's the case, then it would appear that a Standard Rotation (LH) engine is what you want.
So, if you were to view the main shaft being rotated CW (again, if viewing from AFT), then the Prop Shaft will rotate CCW...... and is exactly what you want for a Port Side Engine/Drive.

BTW, the mechanical fuel pumps are available.
If you go to an electric fuel pump, you are now required to have a "Low oil shut-down" system..... which requires a "start by-pass" circuit to be installed.
You may want to re-think the electric fuel pump unless you are willing to install this. It is a USCG requirement!

Is this new Marine Engine block NOT machined for a mechanical fuel pump??????
My thoughts are that a Marine Engine will be machined for one.

Don, an unsolicited comment here, but I'd sure be finding out what caused the engine to sieze up on you before going too far with running this new engine.
If you had water reversion, of some sort, you will want to correct this first, IMO.

Also, I'm hoping that others with more experience on this type of V-Drive chime in!
 
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Don, I believe that you are correct IF your V Drive uses only two (2) gears for FWD!

That is correct the Crusader 4500 only has two gears

BTW, the mechanical fuel pumps are available. If you go to an electric fuel pump, you are now required to have a "Low oil shut-down" system..... which requires a "start by-pass" circuit to be installed.
You may want to re-think the electric fuel pump unless you are willing to install this. It is a USCG requirement!

I looked at the block and it is not machined for a manual pump. We will go electric and even though USCG has no jurisdiction in the Great White North, my mechanic is following the guidelines as stated by the USCG cause I might just venture back into US waters again. I honestly don't know the regs for the CCG but always better safe than sorry.

Don, an unsolicited comment here, but I'd sure be finding out what caused the engine to sieze up on you before going too far with running this new engine.

Rick...suffice to say....there was an incident of vandalism at our marina in the early winter of 2009. I thought my boat was "missed" but apparently it was not. The Port carb was off the engine, the hatch cover was down but not locked..............how does at least 3 quarts of clear water get into the cylinders when the intake manifold was choked with clean rags???

The water was not noticed until we tried to start the engine. Hydro locked and after surgery we could see all the rust in the cylinders......not a drop of antifreeze in the cylinders.

The vandalism effected 9 boats, on blocks outside, some were trashed insidetheir cabins , some had engine parts hammered/crowbarred.....the alleged culprit is an ex-employee who was let go do to the fact that he was lazy.....Police are still investigating and I have added my name to the list of affected boaters. I am talking to my Insurance people.

Pretty sad to see/hear but we all know there are some pretty unhinged people out there......

PS....The marina showroom and head office burned down two years ago but that was proven to have started with an electrical short...the building was very old and basically a tinderbox...they have rebuilt a lovely new building...Grand opening mid June this year !!
 
Don,

I was taken aback by the use of the word " ERGO " a few posts back.Ain;t heard it in some time...Reading further about your vandalized boat REALLY gets to me. It seems there is no shortage of idiots who fail to recognize the rules of a social society. I hope your situation is dramatically improved with your next few posts...You are too nice a guy. By the way, I cleaned my heat exchangers last week and thought of you! Thanks...AL
 
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