Mercruiser 4.3L not going into gear

cory82 · May 26, 2013

i have a 2007 4.3L mercruiser. I was riding along in it yesterday just fine when it suddenly just seemed like it kick out of gear and rev'd up, so I stopped and upon trying to trouble shoot and couldn't get it to go in gear and then the motor started running hot so I had to kill it. I have an impeller replacement kit ordered and will replace it soon, but what would make it kick out of gear like that and not go into gear?

thanks for any help

dubs283 · May 26, 2013

Re: Mercruiser 4.3L not going into gear

cory82 said:
I was riding along in it yesterday just fine when it suddenly just seemed like it kick out of gear and rev'd up ... then the motor started running hot... what would make it kick out of gear like that and not go into gear?

spun engine coupler

when was the last time the drive was off, alignment checked and coupler inspected/greased??

cory82 · May 26, 2013

Re: Mercruiser 4.3L not going into gear

dubs283 said:
spun engine coupler

when was the last time the drive was off, alignment checked and coupler inspected/greased??

I just recently purchased the boat from an individual, and I know everything was running fine last summer. I also know all the bellows were replaced last year, so the drive was off then and aligned when it was put back on, but I don't know if they inspected the coupler. What would it take to inspect/replace the coupler?

dubs283 · May 26, 2013

Re: Mercruiser 4.3L not going into gear

cory82 said:
What would it take to inspect/replace the coupler?

with the engine running, look at the back side where the driveshaft from the drive connects to the coupler - the shaft should be turning, if not the coupler is shot, or...

pull the drive and look at the coupler through the bell housing

to replace the coupler the engine has to be removed from the boat

rickryder · May 26, 2013

Re: Mercruiser 4.3L not going into gear

Could be spun prop hub, engine coupler,u joint, drive and driven gears in upper unit... You'll have to pull the drive and have a look around in there.

dubs283 · May 26, 2013

Re: Mercruiser 4.3L not going into gear

+1 on the upper drive unit gears

seeing as how you experienced an overheat, this also is a suspect issue

cory82 · Jun 2, 2013

Re: Mercruiser 4.3L not going into gear

Update:

I finally got time to check out the problem, I pulled the top plate off the drive and the upper drive unit gears were almost not existent due to lack of lube. So I ordered another upper drive unit, but upon further inspection I found the root cause. the automatic gear lube through transom part that connects the hose from the reservoir to the hose from the drive was broken, so i removed this piece to be replaced

ktbarrentine · Jun 2, 2013

Re: Mercruiser 4.3L not going into gear

If your upper drive is toast, then your lower is too, (or soon will be).:facepalm:

What did your oil (whatever was left) look like when you drained it? Whatever pieces came off the upper gears (metal flakes) will migrate to the lower and trash those gears, too.....Sadly.

dubs283 · Jun 2, 2013

Re: Mercruiser 4.3L not going into gear

cory82 said:
. the automatic gear lube through transom part that connects the hose from the reservoir to the hose from the drive was broken

if the gear lube monitor hose was broken you should have noted the level in the monitor bottle dropping, do you check it often??

cory82 · Jun 4, 2013

Re: Mercruiser 4.3L not going into gear

I had just had a 100 hour service done on it the week before we took it out so I assumed all oil was filled properly. i guess that's what I get for assuming. Also, apparently the guy that had it before me already knew it was broke because the low oil warning alarm for the reservoir was disabled. As for the lower gears, we didn't run it long after it happened and there was oil in the lower so I'm hoping they will be ok, but I will be checking them out

ktbarrentine · Jun 4, 2013

Re: Mercruiser 4.3L not going into gear

cory82 said:
we didn't run it long after it happened and there was oil in the lower so I'm hoping they will be ok, but I will be checking them out

Unfortunately, a few seconds can be a long, long time..... Hoping for good luck for you.
(To paraphrase ST-II Wrath of Kahn.... "By the book.... hours would seem like days"....or is it days would seem like hours...oh I don't know!)

achris · Jun 4, 2013

Re: Mercruiser 4.3L not going into gear

cory82 said:
I had just had a 100 hour service done on it the week before we took it out so I assumed all oil was filled properly.

First mistake. Did you even look under the engine cover before you started the engine? Read your owners handbook... At the start of each boating day... check oil levels, (including gear lube monitor) and loose/ missing parts and a few other things I can't remember off the to top my head. (if you like I can go out and get my handbook, scan it and post it). Once the engine is running, look for oil and water leaking.... All the oil that drained out of the drive and the lube monitor would have been in the bilge of the boat. Did you look in the bilge?

cory82 said:
i guess that's what I get for assuming. Also, apparently the guy that had it before me already knew it was broke because the low oil warning alarm for the reservoir was disabled.

Second mistake. When you bought the boat, did you not check everything was working?

cory82 said:
As for the lower gears, we didn't run it long after it happened and there was oil in the lower so I'm hoping they will be ok, but I will be checking them out

If you don't at least have the gear housing stripped and cleaned and the bearings and gear set THOROUGHLY checked, that will be your third mistake....

Chris..........

rickryder · Jun 4, 2013

Re: Mercruiser 4.3L not going into gear

I mentioned the upper drive and driven gears because.......well I smoked mine last year....don't waste your time on rebuilding what you have...all the metal went into the lower unit and the cost of ripping it down and rebuilding is not worth it....do what I did order yourself a new SEI unit.....look up Sterndrive Engineering in Fla. Really good unit for the $$$

This look familiar????

Mercruiser 4.3L not going into gear

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