What size bolts hold the engine and transmission together? - PeachParts Mercedes-Benz Forum

lietuviai · #1 08-20-2007, 09:10 PM

I'm about to start putting my engine into my 84 300D. I was wondering what size bolts hold the engine and tranny together. I'm even more puzzled that I haven't seen any threads in the intermediate flange (the part the tranny bolts on to) either. Do you need nuts with bolts?
Those of you that have installed engines in your cars, is it better to install them as a unit or install the tranny then the engine or vice versa?
Thanks for any advice in advance.

Stevo · #2 08-20-2007, 09:28 PM

On my 616 they are 17mm (heads) I expect yours are also. two allens hold the starter motor on. I think "pulling or installing" its easiest to have engine and tranny together. You need to tip them about 45 degrees using an adjustable spreader bar.

winmutt · #3 08-20-2007, 09:29 PM

They are big (19mm heads) and come in both bolt and bolt+nut combos. And on the turbo the drivers side upper nut is the biggest PITA. I had to hump the engine and snake my left arm from pass to drivers side.

jshadows · #4 08-20-2007, 09:33 PM

having done tranny R&R and engine R&R I would vote doing it as a unit. Getting underneath the car with a transmission jack is not my idea of a good time. Sure it's a bit more effort to get the tranny past the gauntlet but if you have a good load leveler, good engine hoist and a helper it's not that big of a deal.

Not sure on bolt sizes and nuts. If I remember correctly it's 17mm + some nuts on the 722.1xx and on my 722.361 it was 100% 19mm bolts...I think..might have been 17 but there were definitely no nuts.

jim16671836 · #5 08-20-2007, 09:38 PM

Some of the bolts require a nut... may be best if you use a locknut or a nut with a lockwasher. Some use locktite... red or blue... the 2 allen bolts require a 10mm allen socker/wrench.. it is much easier to install the trans with the engine... be sure and inspect your motor mounts... install the plastic grommets on your trans and on your shifter before installing the trans.. also install the transmission fluid cooler lines before you install the motor/trans in the car.. I think you should use locktite on the 6 torque convertor bolts. Jim

lietuviai · #6 08-20-2007, 09:56 PM

I don't have an engine hoist or any load levelers. I had planned on rigging up a come-a-long with a furniture clamp to act as a load leveler. The clamp has a crank that adjusts one of the ends. You'll have to picture this set up as I haven't put it all together yet. I was very successful unloading the engines with just a come-a-long and chain from my truck when I first got the car.
I'll have to dig through all the coffee cans of bolts to see if I can find the matching bolts. I did find the two hex head bolts that attach the starter so I have a idea how long the bolts need to be.

DeliveryValve · #7 08-20-2007, 10:09 PM

Quote:

Originally Posted by lietuviai

I don't have an engine hoist or any load levelers. I had planned on rigging up a come-a-long with a furniture clamp to act as a load leveler. The clamp has a crank that adjusts one of the ends. You'll have to picture this set up as I haven't put it all together yet. I was very successful unloading the engines with just a come-a-long and chain from my truck when I first got the car.
I'll have to dig through all the coffee cans of bolts to see if I can find the matching bolts. I did find the two hex head bolts that attach the starter so I have a idea how long the bolts need to be.

Well if you do that, I suggest you keep the transmission in the car. I've installed my engine with only using seat belts (I know it is crazy, but people do it at pick n pulls all the time) and kept the transmission in the car. But to get to the upper bellhousing bolts, you just have to angle to engine downward by removing the rear tranny mount and use like 8 feet of rachet extensions and swivels to make it over the tranny. Also you need to jack the car way up to have the leverage to break the bolts loose. But I also installed engines/trans combo with a load leveler. But I wouldn't do it without it if I go that route.

Here is a link of some pics of my engine pull and some others from FI and bgkast. Engine Knock 240D

As far bolts, I recall mine had 17 mm heads, two 10mm hex, and one bolt on the driver side has a nut & bolt combo. I am not sure of the size and can't measure my extra bolts because I am out of town. But here is a link that I posted with the length of the bolts I found.

Loose transmision bolts!!

DeliveryValve · #8 08-20-2007, 10:12 PM

Quote:

Originally Posted by lietuviai

I'm about to start putting my engine into my 84 300D. I was wondering what size bolts hold the engine and tranny together. I'm even more puzzled that I haven't seen any threads in the intermediate flange (the part the tranny bolts on to) either. Do you need nuts with bolts?
Those of you that have installed engines in your cars, is it better to install them as a unit or install the tranny then the engine or vice versa?
Thanks for any advice in advance.

That is because some of the upper bolts are directly bolted to the block, not the rear plate.

lietuviai · #9 08-20-2007, 10:31 PM

I guess I haven't looked well enough at the back of the engine. I've got one block currently attached to my engine stand and it's attached to it with nuts and bolts.

DeliveryValve · #10 08-20-2007, 10:39 PM

Quote:

Originally Posted by lietuviai

I guess I haven't looked well enough at the back of the engine. I've got one block currently attached to my engine stand and it's attached to it with nuts and bolts.

Yikes!

I'd be afraid of warping that aluminum rear plate. I am not sure how much weight the rear plate can take. You really need to attach that heavy engine to the stand directly to the block. I did mine by removing the rear plate and using the four bolt holes for the the attachment of the plate.

lietuviai · #11 08-20-2007, 10:44 PM

The block that's on the stand now is not the good engine that's going into my car. It's a bad block with fried crank and rod bearings.

lietuviai · #12 08-20-2007, 11:08 PM

Quote:

Originally Posted by DeliveryValve

Well if you do that, I suggest you keep the transmission in the car. I've installed my engine with only using seat belts (I know it is crazy, but people do it at pick n pulls all the time) and kept the transmission in the car. But to get to the upper bellhousing bolts, you just have to angle to engine downward by removing the rear tranny mount and use like 8 feet of rachet extensions and swivels to make it over the tranny. Also you need to jack the car way up to have the leverage to break the bolts loose. But I also installed engines/trans combo with a load leveler. But I wouldn't do it without it if I go that route.

Here is a link of some pics of my engine pull and some others from FI and bgkast. Engine Knock 240D

As far bolts, I recall mine had 17 mm heads, two 10mm hex, and one bolt on the driver side has a nut & bolt combo. I am not sure of the size and can't measure my extra bolts because I am out of town. But here is a link that I posted with the length of the bolts I found.

Loose transmision bolts!!

Good advice and links.

sailor15015 · #13 08-21-2007, 12:11 AM

Remember, there are two different bolt lengths. The people that replaced the tranny on the '84 got them in the wrong holes and I was pulling my hair out for six months trying to find the vibrations it caused. I replaced nearly everything rubber in the driveline, just to look under there on day and find two bolts bottomed out with about a quarter inch of the head sticking out, and the others bottoming out with only a thread or two being caught.

lietuviai · #14 08-21-2007, 12:29 AM

Quote:

Originally Posted by sailor15015

Remember, there are two different bolt lengths. The people that replaced the tranny on the '84 got them in the wrong holes and I was pulling my hair out for six months trying to find the vibrations it caused. I replaced nearly everything rubber in the driveline, just to look under there on day and find two bolts bottomed out with about a quarter inch of the head sticking out, and the others bottoming out with only a thread or two being caught.

I was reading the posts in the link about the bolt sizes and it looks like you weren't the only one that had this problem. I actually went back and re-read them thinking one of the posts was yours.