350 CHANGE OUT FROM 305
 

Hey Guys, I haven't been on much, between the Navy Yard and my landscaping business they are running me ragged, But I need info so I'm asking:

Maybe some of you will remember that I'm changing out my 1991 305 for a 1991 350 because of a bad block.

Here's my question??

I'm planning on using my 305 flywheel and harmonic balancer on the 350, does anyone know know if this won't work? They will fit on the 350 crank. I had a auto parts store look up the part #'s for each and they were different. I've asked a chevy guy and another marine mechanic they both said that since I won't be turning over 4500 rpm's this won't bother the engine.
Does anyone know?

350 CHANGE OUT FROM 305
 

Hey Guys, I haven't been on much, between the Navy Yard and my landscaping business they are running me ragged, But I need info so I'm asking:

Maybe some of you will remember that I'm changing out my 1991 305 for a 1991 350 because of a bad block.

Here's my question??

I'm planning on using my 305 flywheel and harmonic balancer on the 350, does anyone know know if this won't work? They will fit on the 350 crank. I had a auto parts store look up the part #'s for each and they were different. I've asked a chevy guy and another marine mechanic they both said that since I won't be turning over 4500 rpm's this won't bother the engine.
Does anyone know?

Re: 350 CHANGE OUT FROM 305
 

check the bolt patern for the flywheel, all small blocks( except the 400) use internally balanced cranks, all the flywheels should inter change as long as it has the correct bolt pattern, they changed the bolt patern when they went from two piece rear main seal to to one piece(85?). There may have been some total weight changes for the flywheel , but they should all( ex. 400) interchange as far as balance, just make sure you use the right starter with the corrisponding flywheel.

Re: 350 CHANGE OUT FROM 305
 

check the bolt patern for the flywheel, all small blocks( except the 400) use internally balanced cranks, all the flywheels should inter change as long as it has the correct bolt pattern, they changed the bolt patern when they went from two piece rear main seal to to one piece(85?). There may have been some total weight changes for the flywheel , but they should all( ex. 400) interchange as far as balance, just make sure you use the right starter with the corrisponding flywheel.

Re: 350 CHANGE OUT FROM 305
 

They should fit. Both motors are internally balanced. If you see any counterweighting on the flywheel or damper, it is for an external balanced motor and won't fit. The 305 and 350 flywheels may have different numbers of teeth, 153 and 168 are common sizes. 168 was older 350s. 153 covered both the 305 and some newer 350's. Both will work, but the starters have different mounts depending on the flywheel. As long as you use the starer that came off the 305, you should be fine.

Re: 350 CHANGE OUT FROM 305
 

They should fit. Both motors are internally balanced. If you see any counterweighting on the flywheel or damper, it is for an external balanced motor and won't fit. The 305 and 350 flywheels may have different numbers of teeth, 153 and 168 are common sizes. 168 was older 350s. 153 covered both the 305 and some newer 350's. Both will work, but the starters have different mounts depending on the flywheel. As long as you use the starer that came off the 305, you should be fine.

Re: 350 CHANGE OUT FROM 305
 

87+ small block chevy's are internally/externally balanced. The balancer should interchange, but the flywheel may not. 87+ 305/350 were neutral balance on the balancer for standard production engines(LT and LS series engines are a whole nother deamon), but the flywheel/flexplate has a counter weight on it for all of the 87+ small blocks. The counter weights were different weights depending on wether or not it was a perfomance engine or not.

I'll dig out my interchange book here in a little while and do some more checking. Do you know the casting number on flywheel?

Re: 350 CHANGE OUT FROM 305
 

87+ small block chevy's are internally/externally balanced. The balancer should interchange, but the flywheel may not. 87+ 305/350 were neutral balance on the balancer for standard production engines(LT and LS series engines are a whole nother deamon), but the flywheel/flexplate has a counter weight on it for all of the 87+ small blocks. The counter weights were different weights depending on wether or not it was a perfomance engine or not.

I'll dig out my interchange book here in a little while and do some more checking. Do you know the casting number on flywheel?

Re: 350 CHANGE OUT FROM 305
 

I went and checked and the regular production(truck style) engines from 87+ use the same bobweight for the counterweight for both a 305 and 350. So you can use your old flywheel from your 305 to a 350. GM PERFORMANCE parts and MERCRUISER both list the same flywheel/flexplate for all of the 1986-2000 5.0L/5.7L gen1 engines.

Re: 350 CHANGE OUT FROM 305
 

I went and checked and the regular production(truck style) engines from 87+ use the same bobweight for the counterweight for both a 305 and 350. So you can use your old flywheel from your 305 to a 350. GM PERFORMANCE parts and MERCRUISER both list the same flywheel/flexplate for all of the 1986-2000 5.0L/5.7L gen1 engines.

Re: 350 CHANGE OUT FROM 305
 

Thanks to all for the info, Both my guys I asked pretty much said the same thing as ya'll, I'm using my flywheel, starter, harmonic balancer. Sounds like everything should be GOOOOD to GO. I'm happy again and the world is at peace in my mind anyway!!!!!

I bet I'm going to have to watch that I don't over rev the motor, I'm not changing out my dual props, tooo much money$$$$$$$.
garage

Re: 350 CHANGE OUT FROM 305
 

Thanks to all for the info, Both my guys I asked pretty much said the same thing as ya'll, I'm using my flywheel, starter, harmonic balancer. Sounds like everything should be GOOOOD to GO. I'm happy again and the world is at peace in my mind anyway!!!!!

I bet I'm going to have to watch that I don't over rev the motor, I'm not changing out my dual props, tooo much money$$$$$$$.
garage

Re: 350 CHANGE OUT FROM 305
 

to make a smoother motor do yourself a favor and buy a fluid damper from Summit for $78

Re: 350 CHANGE OUT FROM 305
 

to make a smoother motor do yourself a favor and buy a fluid damper from Summit for $78

Re: 350 CHANGE OUT FROM 305
 

I hadn't seen one from SUMMIT for $78, this is the cheapest fluid balancer I've found for a small block so far.

http://store.summitracing.com/partde...p;autoview=sku

Re: 350 CHANGE OUT FROM 305
 

I hadn't seen one from SUMMIT for $78, this is the cheapest fluid balancer I've found for a small block so far.

http://store.summitracing.com/partde...p;autoview=sku

Re: 350 CHANGE OUT FROM 305
 

not avail online but in the catalog it is listed or call them and ask for their SBC fluid balancer, i have one on my old Camaro

Re: 350 CHANGE OUT FROM 305
 

not avail online but in the catalog it is listed or call them and ask for their SBC fluid balancer, i have one on my old Camaro

Re: 350 CHANGE OUT FROM 305
 

I thought Fluidamper stopped making dampers for automotive engines and was strictly doing industrial applications. I wish I would have known about that $78 one before I wasted my money on a Chinese pile of junk.

Re: 350 CHANGE OUT FROM 305
 

I thought Fluidamper stopped making dampers for automotive engines and was strictly doing industrial applications. I wish I would have known about that $78 one before I wasted my money on a Chinese pile of junk.

Re: 350 CHANGE OUT FROM 305
 

Hey GNC,

Good to hear you are still kicking, hope you get that baby running soon, the season is.......well never mind, your season never ends down there, but you still need to get on the water.

Re: 350 CHANGE OUT FROM 305
 

Hey GNC,

Good to hear you are still kicking, hope you get that baby running soon, the season is.......well never mind, your season never ends down there, but you still need to get on the water.

Re: 350 CHANGE OUT FROM 305
 

yea man I need to get on the water, I'm having withdraws. Maybe when I retire at the 1st of next year I'll have to only worrry about landscapng and fishing.

I looked at my leave calendar yesterday and I could have gone out 56 days ago and still got a paycheck until I retired.

Re: 350 CHANGE OUT FROM 305
 

yea man I need to get on the water, I'm having withdraws. Maybe when I retire at the 1st of next year I'll have to only worrry about landscapng and fishing.

I looked at my leave calendar yesterday and I could have gone out 56 days ago and still got a paycheck until I retired.

Re: 350 CHANGE OUT FROM 305
 

Got the bilge done and alot of some of the electrical crap I've been wanting to do. I got the trim tabs back on.
I beefed up the truss and installed my vertical braces for the trusses. I lifted the new 350 and set it in the boat. I talked to some boat guys and my old motor was lower in the front than in the rear or level and they tell me mine should be have been level or higher in the front. To get mine level I would have to raise my motor 1 1/2".

Does this seem right to you inbd guys?

If this is right I'm going to have to install blocks between the motor mount and the boat ribs.

Has anyone else added blocks?

Re: 350 CHANGE OUT FROM 305
 

Got the bilge done and alot of some of the electrical crap I've been wanting to do. I got the trim tabs back on.
I beefed up the truss and installed my vertical braces for the trusses. I lifted the new 350 and set it in the boat. I talked to some boat guys and my old motor was lower in the front than in the rear or level and they tell me mine should be have been level or higher in the front. To get mine level I would have to raise my motor 1 1/2".

Does this seem right to you inbd guys?

If this is right I'm going to have to install blocks between the motor mount and the boat ribs.

Has anyone else added blocks?

Re: 350 CHANGE OUT FROM 305
 

You need an alignment tool to see if the front of thengine needs to come up or not. The angle of the engine isn't important, it's wether or not the driveshaft goes into the coupler straight or not that IS important. You need to get an alignment tool and check it, then decide if you need a block or not.

Re: 350 CHANGE OUT FROM 305
 

You need an alignment tool to see if the front of thengine needs to come up or not. The angle of the engine isn't important, it's wether or not the driveshaft goes into the coupler straight or not that IS important. You need to get an alignment tool and check it, then decide if you need a block or not.

Re: 350 CHANGE OUT FROM 305
 

its not uncommon to use blocks, but like Ferm said, its to align the engine with the alignment tool. Do a search for alignment tool, some one on here has one, they might rent it to you. I use mine too often to part with it.

Re: 350 CHANGE OUT FROM 305
 

its not uncommon to use blocks, but like Ferm said, its to align the engine with the alignment tool. Do a search for alignment tool, some one on here has one, they might rent it to you. I use mine too often to part with it.

Re: 350 CHANGE OUT FROM 305
 

I would think that since the 350 and 305 are the same externally that you would put the 350 back in the same location/angle as the old.

The above mokaniks sound like they have your answer.

Re: 350 CHANGE OUT FROM 305
 

I would think that since the 350 and 305 are the same externally that you would put the 350 back in the same location/angle as the old.

The above mokaniks sound like they have your answer.

Re: 350 CHANGE OUT FROM 305
 

The alignment tool ya'll talk about, I don't think the Volvo has one because the bell housing has the drive shaft spline already installed. I don't know how you would use one with the drive shaft spline in place. On the volvo it has to be installed before you put the bell housing on the motor.

Re: 350 CHANGE OUT FROM 305
 

The alignment tool ya'll talk about, I don't think the Volvo has one because the bell housing has the drive shaft spline already installed. I don't know how you would use one with the drive shaft spline in place. On the volvo it has to be installed before you put the bell housing on the motor.

Re: 350 CHANGE OUT FROM 305
 

The alignment tool I'm talking about basically slides in where your driveshaft does so that the engine and gimbal bearing are aligned properly. I'm 99.9% certain that VOLVO uses them. You have to remember what is important is that when the driveshaft slides in through the gimbal that it goes straight into the coupler bolted to the flywheel. Solid shafts don't like to be flexed, and would eventually break the transom or driveshaft from binding(if you could even get your outdrive on).

Re: 350 CHANGE OUT FROM 305
 

The alignment tool I'm talking about basically slides in where your driveshaft does so that the engine and gimbal bearing are aligned properly. I'm 99.9% certain that VOLVO uses them. You have to remember what is important is that when the driveshaft slides in through the gimbal that it goes straight into the coupler bolted to the flywheel. Solid shafts don't like to be flexed, and would eventually break the transom or driveshaft from binding(if you could even get your outdrive on).

Re: 350 CHANGE OUT FROM 305
 

Ferm
my gimbal bearing is on the outdrive shaft of the outdrive and not on the shaft from the flywheel.

You cant align the the motor/shaft that way on my volvo because that would mean I would have to pull the motor all the way back out just to install the drive shaft and bell housing

Re: 350 CHANGE OUT FROM 305
 

Ferm
my gimbal bearing is on the outdrive shaft of the outdrive and not on the shaft from the flywheel.

You cant align the the motor/shaft that way on my volvo because that would mean I would have to pull the motor all the way back out just to install the drive shaft and bell housing

Re: 350 CHANGE OUT FROM 305
 

I'm not familiar with VOLVO but I know on a MERCRUISER the driveshaft splines go into the coupler and right in front of the u-joints is where the gimbal bearing rides. I know the alignment tool i have is also listed for a VOLVO.

Re: 350 CHANGE OUT FROM 305
 

I'm not familiar with VOLVO but I know on a MERCRUISER the driveshaft splines go into the coupler and right in front of the u-joints is where the gimbal bearing rides. I know the alignment tool i have is also listed for a VOLVO.