Logo
FULL SITE MENU

Mercruiser 4.3L Ser# 1A060945 engine mounts

T

trynhooker

Regular Contributor
Hopefully someone will chime in quickly with an answer.

Trying to remove port engine mount (looking at motor) to get to the freeze plug.
All the pictures I've seen for the mount show there are 4 - M10 x 30 screws, 2 - studs and 2 - nuts connecting mount to block.

However, this 2009 unit has 2 studs and nuts on the port side and one screw. The port mount also holds the fuel components.
After pulling the fuel bracket off, I found the stud has a unique nut threaded on.
Or is that nut made onto the stud?

Eitherway, the nut is strange, it has a v-cut then a flat around the nut probably 5 times..Looks kinda like a 8 point socket except every other notch is flat or something like that..

Does anyone know if there is a special tool required because a socket will not fit.

Thanks all
 
trynhooker, that may very well be a torque head bolt. (Don't sound like a nut) I think you may be able to use a 12 point metric socket on it if you can fit it perfectly. Also, are you saying the pictures your looking at says there are 4 m10x30 (meaning metric 10mm bolt with 30 threads per inch?) Gotta see a picture of what you got to help you any further. best of luck, Tom
 
Tom,

After looking at the manufacture pics a little longer, it seems that these studs have a nut made in the middle so you can torque the stud into the block. It's def not a torque head bolt because the stud extends past where the nut is, and then you put another nut pc. 8 on which holds the engine mount on the block.

In this pic.... https://www.mercruiserparts.com/Sho...9.png&inbr=12833&bnbr=280&bdesc=Engine+Mounts you can see stud pc. 3. The only difference is that this engine has 2 studs on the port mount as described in my original post.

I had a 11/16 on it but after turning it very hard it let go.. Also, pc.3 in the pic above doesn't resemble the actual nut I'm referring to but I can't find a real picture of it anywhere..
 
Trying to remove port engine mount (looking at motor) to get to the freeze plug.
Click to expand...

Ayuh,... The portside of the motor don't change, regardless which way your Lookin'...
You're workin' on the Starboardside of the motor....

I donno what kinda nut, or stud yer lookin' at,... Got a picture,..??
Every 1 I've seen is either a standard capscrew, or the stud/ nut comb like item #3 in your link...
It's gonna turn hard, as the weight of the motor is on it...
 
bondo...ur right of course..stbd it is
I just explained it for those who may get confused...hehe

I can't get a pic of it..ever tried taking a pic with an iphone...doh... it's all upside down and you can't look at phone screen cos you can't get ur head in there.

Anyway, I would think it would have just been a typical nut made into the stud but Merc (or GM) decided to make something new...Maybe there trying to sell a new stud removal socket that fits it..but I can't find anything like it
 
You can not remove the motor mount without lifting the engine up a bit to take the weight off it anyway.

get the engine secured to a hoist and relieve the pressure on the mount. Then maybe you can loosen the bolt/stud/nut what ever it is.

You will need to do this anyway in order to remove the mount without the block falling to one side

even if you could get the mount off without the support something or someone might get hurt..............

Also get a flash light and snap a pic with you Iphone............
 
crow bar and some flat wood to secure the motor. Just don't pry in the middle of the oil pan.

Flat wood between the motor and the crowbar.

I swear i must be having a brain fart cause i don't see any problem, unless what you have is rusted.

I also would like to a see pic of what is actually there. I just got finished with my friends 4.3 his is a 09' also.

We used a 2x 4 between the deck and the crowbar to get better leverage.
 
using wood and a crow bar is very dangerous................

If the crow bar were to snap back it could easily break a hand or worse..........

Chief!!!! For the average guy here they need to be given propper intructions with safety in mind..........Especially trying to lift an engine block in a boat with wood and a crow bar.........................................

I fully understand that many of us would and most likely have done this when needed but that is US not "them".

We must be careful with certain types of advice........
 
I figured out what kind of nut it is. It is actually needs a Torx Head Socket. This is not the typical Torx head screw were all used to.

I tried using a flashlight and my phone but could not get the picture.

Another mechanic friend of mine has a set of Torx head sockets and sent me a pic of the socket. Problem is no one carries one large enough around here..I can get an 11/16 socket over it so it's roughly 17.4 mm.

This is my friends pic of the socket. IMG_0303.JPG
 
Ok maybe a saw horse straddling the engine bay with a hoist.

I don't want anyone getting hurt using my advice.

I had my son the football player who carried a fridge up the basement stairs himself pushing on the 5 foot pry bar.

9 of his friends and himself carried the football coach's car into the gym.
 
Hey at least it's not Whitworth! I assume you are not working on your own boat otherwise you'd have probably already gotten that thing out (without regard for saving it) with the idea that you'd replace it with something less weird.
 
Found out today that a 16mm 12-13 pt or whatever it is fits that nut..Ended up putting the plug back in without removing the mount anyway..
I'm good like that...lol

Also found out from Mercury that Mercruiser doesn't supply the studs for the block mount side nor the bolts that hold the mount to the stringer...Those are boat manufacturer supplied items..
 
Go to a hardware store/automotive store with the bolt in hand and replace them all with standard/metric hex head bolts for the next time........grade 8 I would suggest for a motor mount.
 
trynhooker, I figured it was some sort of torque head. I told you a 12 point would work, but that is generally on the regular torque head. That's good you got it out! I would definitely replace those darn things with something with a regular metric head and launch the other things into a trash can! lol
talk to you later, Tom
 
I was able to get pics with the iphone..Helps that I did this during the daylight rather than almost dark like the first time
IMG_0311.JPGIMG_0306.JPG

Thanks for all the suggestions also...
 
Back
Top