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New starter/trunnion interference

bobct

Advanced Contributor
The perverbial snowball effect :)

Bad cutless bearing--->realigning/re-shim the strut---->new engine mounts---->might as well replace my 25 yo starters while I'm in there.


I got two brand new Arco starters. The problem as you can see in the pic is the trunnion just makes contact with the body of the starter so I can't quite get it installed. I looked at the other engine and it's fractions away on that side too. I've only done a very rough/eyeball side to side alignment and so maybe the new strut position moved the engine over a hair which led to my issue.

There's plenty of meat on the bone so to speak so I was thinking of removing the mount and grinding maybe an 1/8" off the end of the trunnion. Anyone else had this issue?

Bob
 

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Bob, I can't see what you are asking about via your photo. Also, I am not familiar with the term "trunnion" being used with Starter Motor.
Perhaps another photo and more info.
These are Inboard starter motors.....correct?
You mention "25 yo starters".... did you replace with Bendix style..... or solenoid lever action style?


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If you modify the starters, then there goes any warrantee. If this is the case (can't tell from your description), I'd go with the "correct" starters that fit.

Jeff
 
Before you remove anything from the end of the trunnion why can't you finish the engine alignment and see if you then have the needed clearance? Removing 1/8" from the end of the trunnion most likely is fine as it will still have enough left the engage the body of the motor mount. You chose.
 
I've been doing mechanical work since the mid 60's, but I am not familiar with what you are calling a "trunnion" pertaining to a Marine Starter Motor.

Here's a parts break down for the older Bendix Drive style motors.

Here's a parts break down for the solenoid lever action style motors.

Is "trunnion" being used in slang term language by chance?
I don't care what we're calling it, I'm just curious as to what you're talking about!

And again..... you mention that these are brand new Arco starters, but are we talking about a Bendix style, or solenoid lever action style starter motors here?

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Rick/Jeff,

The "trunnion" is the part of the Crusader mount that the engines slides side/side on. The flat part that is circled in the pic is the end of the trunnion, closest to the engine block. I verified that these are the correct starters for the 454 Crusader. The other engine still has the original starter installed and it's an 1/8" (if that) from touching too. So, that leads me to believe this is model specific and not something anyone would notice if either the alignment were a fraction to the port side or there was another 1/4" between the stringers...

My proposed fix is to grind about an 1/8" off the end of the trunnion which would do the trick.
 
Rick.. forgot that part of your post. These are solenoid starters, the Arco #'s are 30456 and 30457

http://www.arcomarine.com/xhtml/30456-30457.pdf

Here's a link.

CRU97905.jpg













The "trunnion" is sticking out above.....
 
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Oh that Trunnion.......... Duh! :eek:

Sorry guys! I need to go back to school.... either that, or it looks like My turn in the barrel again, eh? :D :D :D
Sheesh.... I hate being in the barrel!

(keep this under your hats, will ya?) :D

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Yep, that's the guy! I learned it from one of Mark's posts. I would have called it that "slidey thing" myself.
 
Bob, I should have picked up on this with the thread title....... New starter/trunnion interference.
The slash should have been my clue. :D

Bob, since this one interfears with an engine mount, I'll assume that these are engine block mounted starter motors... not Borg Warner flywheel cover mounted. The Delco solenoid lever action like this one?


gm_marine_starter.JPG


Perhaps this is a bit late in the game here.... but IMO, this day and age it's rather silly to not use one of the HTGR/PMGR motors.
They are shorter, smaller in diameter, lighter weight, and kick A$$ over the OEM style.
The armature spins at approx 3 X's that of an OEM, the gear reduction gives these more torque than the OEM, and the end result is faster cranking RPM.
Because of the smaller size, perhaps these would not cause the need to modify the engine mounts.
Here's one in the Arco brand.

images


Just a thought and FYI on that. :D

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Bob: If the rear mount's lag bolts are centered in the stringer, then the engine bed was built correctly. Your approach will be much easier than plugging the existing holes and redrilling new ones. you only have to provide relief on the upper half of the trunnion. I'd be inclined to remove the material using a bench grinder. To ensure no stress induced issues later on, smooth (radius) the edges around the perimeter of the ground out area...

PS - I thought your description, with the pic, was more than adequate...nothing like an accurate description to convey the issue. :)
 
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Before you remove anything from the end of the trunnion why can't you finish the engine alignment and see if you then have the needed clearance? Removing 1/8" from the end of the trunnion most likely is fine as it will still have enough left the engage the body of the motor mount. You chose.

I stand by my original post. You may try removing the material using a 4" Grinder with a metal cut off wheel. Maybe do it in the boat if you have access or remove it from the boat to be safer.
 
PS - I thought your description, with the pic, was more than adequate...nothing like an accurate description to convey the issue. :)
Mark, you're a better man than I.......... I was having difficulty with the photo.

I would still not mind seeing a few more as to get a better perspective of it.


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Rick,

I looked at the pic again and can how it's confusing. I don't know if it's obvious but it's actually a picture of a mirror I'm holding, the only way I could get the pic. The only part of any relevance is inside the red circle. Yes, the Delco starter is exactly what it looks like. I don't believe the smaller ones are on option for the 454's but that doesn't mean that someone else might have them as an option. The Arco's get good feedback so I guess I'll stick with them since I already have them. Now that I know about this minor clearance issue, I'll take care of that in advance on the other engine.

I removed the entire mount and then ground off about 1/2" from the end of the trunnion which basically makes it flush with the bracket. It's impossible to move the engine any further to one side so the trunnion will always be "inside" but won't have any significant overhang. I did it off the boat since grinders throw so many sparks.

Bob
 
Bob, me in blue text..........

Rick,

I looked at the pic again and can how it's confusing. I don't know if it's obvious but it's actually a picture of a mirror I'm holding, the only way I could get the pic. The only part of any relevance is inside the red circle.
At first I did think "mirror" but wasn't sure. That makes sense to me now.

Yes, the Delco starter is exactly what it looks like. I don't believe the smaller ones are on option for the 454's but that doesn't mean that someone else might have them as an option.
Yes, the HTGR/PMGR starter motors are available for the BBC's just as they are for the SBC's..... the difference is wattage in KW.

The straight across bolt pattern is for the 153 tooth flywheel ring gear....... and the staggered bolt pattern is for the 168 tooth flywheel ring gear.
You probably have the 168 tooth ring gears..... which means the staggered pattern motor.


The Arco's get good feedback so I guess I'll stick with them since I already have them. Now that I know about this minor clearance issue, I'll take care of that in advance on the other engine.
Well, the HTGR motor would likely solve your problem.

I removed the entire mount and then ground off about 1/2" from the end of the trunnion which basically makes it flush with the bracket. It's impossible to move the engine any further to one side so the trunnion will always be "inside" but won't have any significant overhang. I did it off the boat since grinders throw so many sparks.
You mean that fuel vapors are flamable???? :D :D
That was a good decision!:D

Just for fun, here's a HTGR motor for a BBC for under $100.

12 vdc Std Rotation
3 horse power equivilant
fits applications with 168 tooth flywheel 283, 327, 350, 383, 396, 427, 454
for use up to 18:1 C/R engines

$(KGrHqN,!k8E647N-zo!BO)Zd0BMzQ~~60_12.JPG
 
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Bob, me in blue text..........



Just for fun, here's a HTGR motor for a BBC for under $100.

12 vdc Std Rotation
3 horse power equivilant
fits applications with 168 tooth flywheel 283, 327, 350, 383, 396, 427, 454
for use up to 18:1 C/R engines

$(KGrHqN,!k8E647N-zo!BO)Zd0BMzQ~~60_12.JPG



Of course that is a bottom mount starter in the picture. Is that type of stater available for a "Flange Mount" application that common on most inboards?
 
2X on the mounting issue!

I saw one for sale, once...no reverse rotation option and, for almost $400, I'll stay old school...if it works, why mess with it?

Bob - Glad your issue is resolved...BTW, the mirror was kinda obvious to me - now if you would have cropped the picture....
 
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Of course that is a bottom mount starter in the picture. Is that type of stater available for a "Flange Mount" application that common on most inboards?
If you are asking if a HTGR/PMGR starter motor is available for an I/B application (as in a Borg Warner flywheel cover AFT install), then yes...... they sure are, and in both Std LH and Rev RH engine rotation, and have been for quite some time.
In fact, I think you'd be hard pressed to find a current OEM starter motor that was NOT HTGR/PMGR these days.
Chrysler pioneered the gear reduction starter motor back in the late 50's. It took until roughly the mid 90's for everyone else to get on board with the idea.


I'll stay old school... if it works, why mess with it?
These Armatures spin approx 3 x's that of the older non-reduction.
Torque to the ring gear is greater.
Faster cranking RPM.
Some even draw less amps for the same work load.
Over-all size is smaller.
Most are several pounds lighter as well.



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