Bravo drive shifting delay issues advice needed

[mr300z87]

Yesterday I started a thread in the non repair io forum regarding the serial no. on a Bravo 1 drive that I had purchased and now I think it has become a repair issue. My boat is a 1989 invader with a 5.7 Bravo 2 with 240 hours on it I bought it from the second owner of 18 years. The engine runs great and the boat performs well but I have found that on first start up(cold) there is a 10 to 20 second delay before engaging forward gear. After running for a while seems to work ok. Shift cable was adjusted per merc manual with merc tools while doing the bellows back in June. Also gear lube replaced with Merc hp gear oil after pressure test passed. I have research this problem and found similar Bravo drive issues although not exactly the same saying the clutch mechanism is worn. I think I also read that Merc revised the clutch design because of failures.

Last week a found a used Bravo 1 drive of similar vintage for a reasonable price (Bravo drive are expensive) with a 30 day warranty. After draining gear lube, pressure test and new merc hp gear lube I installed the drive and ran on the hose. What I found was this drive behaved the same way only the delay shift was in reverse (came off a boat with twins left rotation drive maybe?). Has anyone experienced this behavior on Bravo drives? I also noticed the top cover of the B1 drive got a little warm while running on the hose is this normal? Never felt the B2 drive top cover.

Need some adivice as to what to do next, should I try and return the B1 and spend the $s on getting my B2 rebuilt? Use the B1 until it fails then rebuild the B2? The boat is in great condition and I plan to keep it for a while but even a new Bravo upper is more than I paid for the whole rig. Btw the B2 serial # is oc505291 and there is no serial # on the B1 which was the reason for my original post yesterday. Unfortuanly my water test of the B1 was postponed. Should I even test it on the water or am I asking for trouble?

Rumor has it that SEI is working on a Bravo upper. Fingers crossed.

As always thank in advance for the help.

Mike

 

[Bondo]

Re: Bravo drive shifting delay issues advice needed

Yesterday I started a thread in the non repair io forum regarding the serial no. on a Bravo 1 drive that I had purchased and now I think it has become a repair issue. My boat is a 1989 invader with a 5.7 Bravo 2 with 240 hours on it I bought it from the second owner of 18 years. The engine runs great and the boat performs well but I have found that on first start up(cold) there is a 10 to 20 second delay before engaging forward gear. After running for a while seems to work ok. Shift cable was adjusted per merc manual with merc tools while doing the bellows back in June. Also gear lube replaced with Merc hp gear oil after pressure test passed. I have research this problem and found similar Bravo drive issues although not exactly the same saying the clutch mechanism is warn. I think I also read that Merc revised the clutch design because of failures.

Last week a found a used Bravo 1 drive of similar vintage for a reasonable price (Bravo drive are expensive) with a 30 day warranty. After draining gear lube, pressure test and new merc hp gear lube I installed the drive and ran on the hose. What I found was this drive behaved the same way only the delay shift was in reverse (came off a boat with twins left rotation drive maybe?). Has anyone experienced this behavior on Bravo drives? I also noticed the top cover of the B1 drive got a little warm while running on the hose is this normal? Never felt the B2 drive top cover.

Need some adivice as to what to do next, should I try and return the B1 and spend the $s on getting my B2 rebuilt? Use the B1 until it fails then rebuild the B2? The boat is in great condition and I plan to keep it for a while but even a new Bravo upper is more than I paid for the whole rig. Btw the B2 serial # is oc505291 and there is no serial # on the B1 which was the reason for my original post yesterday. Unfortuanly my water test of the B1 was postponed. Should I even test it on the water or am I asking for trouble?

Rumor has it that SEI is working on a Bravo upper. Fingers crossed.

As always thank in advance for the help.

Mike​

Ayuh,.... The Bravos All use the same Upper,... Just the lower units are different....

 

[QC]

Re: Bravo drive shifting delay issues advice needed

I'm just surprised you have a boat that works well with a Bravo 2 and then a 1. Seems odd to me.

 

[mr300z87]

Re: Bravo drive shifting delay issues advice needed

Bondo I know all upper are the same. My question is regarding the shifting issue? I was hoping the B1 was good and would keep me going for the rest of the season. Can a newer style upper (oil return hole) be used with an old style lower (no oil return hole)? I know the lower can have the oil passage pluged.

QC It is a 21 ft cuddy cabin originally equipped with the B2 2.0 to 1, 23p prop. (still questioning the original owner and I have docs to confirm B2). This boat never should have been equipped with a B2 and apparently the original owner had to fight with the dealer to have it installed. performance is good jumps out of the hole great and tops out at 43 mph. I have yet to water test with the B1 1.5 to 1 19p prop to get a base line. running a prop calculator shows similar performance

The issue here is not performance but shifting delay and the future reliability of the drive.

 

[Don S]

Re: Bravo drive shifting delay issues advice needed

Disconnect the lower shift cable at the engine. Start the engine and shift the drive using the cable and see if you get the delay then. With wear in the shift cable it may just be an issue of not going all the way into gear and just the vibration of the engine finishes the shift.

 

[mr300z87]

Re: Bravo drive shifting delay issues advice needed

Don, Thanks for the tip as I never thought about doing that. I will give it try later today or tomorrow and post my findings. That would be a kick in the butt if it was just the cable. When you say wear in the shift cable what wears out?

 

[Bondo]

Re: Bravo drive shifting delay issues advice needed

Don, Thanks for the tip as I never thought about doing that. I will give it try later today or tomorrow and post my findings. That would be a kick in the butt if it was just the cable. When you say wear in the shift cable what wears out?

Ayuh,.... The inner cable wears a grove in the outer casing....

It causes a shorter travel, due to the slop...

 

[mr300z87]

Re: Bravo drive shifting delay issues advice needed

That makes sense, and the cable is definitely cheaper than a Bravo upper rebuild . But why i the the delay going into forward on the B2 and reverse on the B1. Tolerances slightly different? If it is the case I will need to ream out the bell housing to install the new style cable. Correct?

 

[Don S]

Re: Bravo drive shifting delay issues advice needed

Kind of hard to answer WHY something is happening, when you don't even know WHAT is causing the issue. But a WAG would be the insides are slightly different between the two drives, and you was shifting both with the same tired shift cable.
Have you even checked the adjustment of the cable or did you go right to replacing the drive?

 

[boatguya1]

Re: Bravo drive shifting delay issues advice needed

Ayuh,.... The Bravos All use the same Upper,... Just the lower units are different....

I'm sure you know this, but want to avoid confusion for others. You can't use the upper from a newer Bravo drive on the lower from an older Bravo drive due to differences in the oil passages. When you try to fill the drive the oil will end up on the ground.

I can't remember what year the change occurrs and am to lazy to look it up.

 

[mr300z87]

Re: Bravo drive shifting delay issues advice needed

When I did the bellows back in June I adjusted the lower cable with the Merc tools and the instructions in Merc manual 11. Did not get a chance to run it today and manually move the cable. If it turns out to be the cable which drive is better suited for my 21 foot cuddy cabin. B1 or B2 since I now have both

Boatguy, that is what I was referring to in post 4. I have read that the oil passage can be plugged on the lower so a miss match could be used. not sure if the same goes for the upper.

 

[Don S]

Re: Bravo drive shifting delay issues advice needed

Today, B2 drives are normally used on bigger heavy cruisers with a top speed of 45 mph or less. But in 89 (second year of the Bravo drives) the Bravo 2 was the only drive available on the 5.7L engines.

 

[mr300z87]

Re: Bravo drive shifting delay issues advice needed

Well that explains the B2, I would assume back in 89 an 5.7 in a 21 ft boat would have gotten an Alpha and the original owner must have wanted the Bravo so B2 is what it got. Thanks for all the info.

 

[mr300z87]

Re: Bravo drive shifting delay issues advice needed

This morning I did as Don suggested and disconnected the lower shift cable so I could shift the drive manually B1 drive. My B2 is in the garage . I feel my results were inconclusive, first shift no wiggling of the cable 30 second delay before reverse engaged, Prop spins slow then after 30 second it engages and spins normal speed. No delay at all in forward. Second shift wiggled cable in and out once it stopped, delay shorten to 2 to 3 seconds. Adjusted cable 1 turn out re mounted cable to shift plate delay varied between 0 to 20 seconds. Spent the next 15 min or so shifting in and out of forward and reverse manually, I would wiggle the cable in and out at the stop and I would consistently get a 1 - 3 second delay. I did notice about 1/8 to 1/4 in of movement in the cable is that normal. Other than this issue the drive seem to run quiet and smooth.

Not sure where to go from here.

 

[Don S]

Re: Bravo drive shifting delay issues advice needed

Did you still have the cable attached to the shift bracket? You need to remove the cable from the bracket, hold the outer cable with one hand and move the inner cable with the other hand.

 

[mr300z87]

Re: Bravo drive shifting delay issues advice needed

That is exactly what I did.

 

[Don S]

Re: Bravo drive shifting delay issues advice needed

Then it's time to take the drive apart and find out what the problem is.

 

[mr300z87]

Re: Bravo drive shifting delay issues advice needed

Reading this old thread very similar issue leads me to believe the issue is the cone clutch. What else inside the gear case would cause as there is not much to it?

http://forums.iboats.com/showthread.php?t=488117

Since the B2 (original drive standard rotation) delays in forward, clutch is worn out in forward direction and the unknown used B1 delays in reverse (could have been the LH rotation drive of boat with twins it came off) the clutch would wear in reveres if used as a standard RH rotation drive. This is an assumption.

I have read through the dis-assembly and assembly process a few time in manual 11 most of which I believe I am capable of, with the purchase of a few tools, the part that scares me the bearing pre load. Any ideas it would cost I know the gear/clutch assembly is $1500. Not sure if it is worth fixing the boat was only $3200.

 

[Fun Times]

Re: Bravo drive shifting delay issues advice needed

Typically to help solve this kind of problem on your original bravo 2 drive you would need to order and install mercruiser part number 43-883473A4.

Also your going to need new thinner thrust bearing shim races to compensate the new gear set. The shims do not come with the gear set due to different sizes.

Your bravo 2 should have had a gear ratio of 2.00:1 when sold new.

You can find the thrust bearing shim races part numbers on page 5 in the service bulletins available online for the do it yourselfers either here, http://www.boatfix.com/merc/Bullet/01/01_17.pdf or to the right of item number 24 in the link below.
http://www.mercruiserparts.com/Show...r=70&bdesc=DRIVESHAFT+HOUSING+AND+DRIVE+GEARS

There are a number of things inside your upper drive unit that will cause a delayed shift and merc part number 43-883473A4 now covers all of them. In the past on you're older Bravo 2 drive, one of the items may have been the cone clutch dubs283 mentioned about,
http://www.boatfix.com/merc/Bullet/91/91_26.pdf

boatguya1, I believe was talking about this back in 91.
http://www.boatfix.com/merc/Bullet/91/91_20.pdf

Yes, your theory of LH rotation is possible.

Also while you're doing all of this, you may as well go ahead and do a new style lower shift cable to help have the smoothest shifting available.

Good luck.

 

[mr300z87]

Re: Bravo drive shifting delay issues advice needed

Thanks for the info fun times, have you ever done one? Question I read somewhere that a newer lower can have the oil passage plugged to work with and older upper. Could I not do the same to an newer style upper to use with my older lower? Why are the Bravo drives so expensive.


I think my first step is to return the B1 drive and then concentrate on the original B2 as its over all appearance is great as is the rest of my 23 year old boat. The seller of the B1 gave me a 30 day warranty and seemed to run a legit business so i am hoping to get my money back. The boat ran good all summer and since boating season is ending in a couple of weeks here in NJ, plus my daughter's soccer season starts next weekend game every Sunday til thanksgiving. The B2 should hold up for 2 maybe 3 more outings. Going to make some calls to see what it will cost for a rebuild on my upper. I am a fair mechanic and have done engine and trans swap but gears and bearings with preload scare me as doing the drive wrong could be a very costly disaster.