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255a engine 280 outdrive questons

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mrnkc130

Member
Hello all, im new to volvo outdrives and inboard motors as well for that matter. I stumbled across this site while researching parts etc on a boat i was recently given and have to say I'm impressed with the community's knowledge!
I'll post some pictures shortly but id appreciate any help with ID of my motor and outdrive as well as suggestions.

I was given a 1978 Sea Ray SRV240 from a family member, the boat is in really quite good condition and was running when parked in 2015. The rear portion of the cover was damaged at some point and some cats got in as well, so there was some cleaning and wood refinishing that needed done and I've gotten alot done in that department. I was hoping to change oil and rubber hose impeller etc and fire this beast up but when pumping out the crankcase i found about 2 qts of water in there. I pulled the heads and everything but one cylinder looked good, some rust one near the top but i may be able to hone it and be ok. with that much water in there though im pulling the motor to make sure the crank wasn't sitting in water and (hopefully) just clean everything hone, rering and new gaskets. Anyways, if you'd be so kind to divulge some of your knowledge i do have some questions!

valve covers say "volvo penta 255a" i havent much about this at all, block numbers say its a 68-70 Chevy 350, its has .60 over pistons (i did find on rebuild receipt for engine cicra 1999) and it has a holley marine 4bbl card and an adapter plate- carb #'s indicate it was for a 351W ford. The boat was all raw water cooling, i have a marine heat exchanger so i think during this process I'm going to hook that up and make it a 1/2 closed system. Seems like a fairly simple project and the benefits seem worth it to me.

the sterndrive as a "280" id plate on the removable cover, the billows need replacing and some wasps had made a home in the outdrive intake and exhaust inlets. the inside of the outdrive only has a yellow sticker and no ID plate that i can find. the outdrive oil was clean and clear and i could tell the system was sealed.

-does this sterndrive take 90w marine gear oil? or 30w engine oil? recommendations or type brand?
-with engine out should i pull the rest and go thru it? new bearings, change shield seal? (shield has sealant all around outboard edge although no indication its leaking) there was some oily gunky stuff in the drive bellow about 2 ounces. I also broke one bolt taking the outdrive off but i can retap that i think, the bolt that holds the side gudgeon pins in.
-for putting stern drive back on i see its easier to remove the transmission and do it in 2 parts, anything special about that procedure besides remove and replace (with gear oil drained)? some kind of shimming procedure or something?
-what transom shield is it i have? i see some very cheap online and some very expensive.
-part number for hose on transom shield the exits down at the 5oclock position? or suitable replacement hose for this.


Im excited to get this boat back on the water (freshwater murky texas lake) that you all in advance for any help and advice, pictures coming shortly.
 
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mrnkc130 said:
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valve covers say "volvo penta 255a"
The AQ 255 is a marinized SBC engine.

i havent much about this at all, block numbers say its a 68-70 Chevy 350, its has .60 over pistons (i did find on rebuild receipt for engine cicra 1999) and it has a holley marine 4bbl card and an adapter plate- carb #'s indicate it was for a 351W ford. The boat was all raw water cooling, i have a marine heat exchanger so i think during this process I'm going to hook that up and make it a 1/2 closed system. Seems like a fairly simple project and the benefits seem worth it to me.
Use caution when converting a previously Raw Water Cooled engine over to a Closed Cooling System.
Rust scale is you enemy, and may build up in the lower section of the Heat Exchanger's tube bundle.

the sterndrive as a "280" id plate on the removable cover, the billows need replacing and some wasps had made a home in the outdrive intake and exhaust inlets. the inside of the outdrive only has a yellow sticker and no ID plate that i can find. the outdrive oil was clean and clear and i could tell the system was sealed.
In 1978 there's a good chance that it is a 280.
All of the rear shift mechanism covers (of this style) interchange, so I'd not go by that alone.

-does this sterndrive take 90w marine gear oil? or 30w engine oil? recommendations or type brand?
30W engine oil only in the 280 s/p.
It need not be detergent oil.

Heavy gear oil may damage the slinger pump impeller drive pins.
If it had heavy gear oil in it, you will want to test the slinger pump.

-with engine out should i pull the rest and go thru it? new bearings,
Yes, install new PDS bearings and seals.
Do a search here and find one of my posts regarding Volvo Penta PDS bearing replacement.
It will give you the procedure and the industry standard part numbers for the bearings and seals.

TIP... when you pull the engine out, remove the four lag bolts and leave the mounts attached to the engine.

change shield seal?
Those would be the two large rubber cushion rings.
The inner ring should be new. It provides the water seal, as well as 1/2 of the rear engine isolation.

(shield has sealant all around outboard edge although no indication its leaking) there was some oily gunky stuff in the drive bellow about 2 ounces. I also broke one bolt taking the outdrive off but i can retap that i think, the bolt that holds the side gudgeon pins in.
Ouch! These bolts thread into thread inserts.
DO NOT chase the threads with a thread cutting tap!
In the future, use propane torch heat on the female threaded areas before attempting to remove any fasteners.


-for putting stern drive back on i see its easier to remove the transmission and do it in 2 parts,
Yes, that is correct!
When going either way, pull transmission first.... install it last.

anything special about that procedure besides remove and replace (with gear oil drained)? some kind of shimming procedure or something?
When removing the transmission, be sure to inventory the shims, and make sure that they go back in as they were.

-what transom shield is it i have? i see some very cheap online and some very expensive.
If you have this style exhaust manifold....................
4948.jpg

.... you will have a double exhaust relief transom shield.
This transom shield is very difficult to find these days.

Im excited to get this boat back on the water (freshwater murky texas lake) that you all in advance for any help and advice, pictures coming shortly.

Pictures would be very helpful.
Click to expand...
 
OK, now that I can see your photos, you have an AQ200D or an AQ225D exhaust system.
The transom shield is a single exhaust relief style, and is much easier to find.

Those exhaust manifolds have served their time.
I would replace them with 3" Barr.

I also notice that you are missing the prop shaft ring anode.

The ignition distributor may be an automotive unit. If so, that needs to replaced.

The fuel filter is old school. I would replace that as well.

You also have the old school belt driven Sherwood seawater pump.
These often cause an owner to defer impeller maintenance due to the time required and the difficulty to access the impeller.
If you replace the exhaust manifolds, you will be removing the Sherwood seawater pump mounting bracket.
This allows the use of the much better Johnson F5B-9 crankshaft pump.
The F5B-9 will outlast the Sherwood 10 to 1 or even more.

shopping




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Thank you so much RicardoMarine! I added some pictures probably while you were responding. I apologize for my lack of posting technical knowledge. i could only seem to post 1 picture at a time and as a new reply each time.

Use caution when converting a previously Raw Water Cooled engine over to a Closed Cooling System.
Rust scale is you enemy, and may build up in the lower section of the Heat Exchanger's tube bundle
I had planned on cleaning the engine and intake as thoroughly as possible once out of the boat, hopefully that will remove a good portion of that, but perhaps i'll add a strainer or something, good point. I did notice alot of scale on the water jackets of the heard etc, this was (atleast for the last 15 years) a fresh water boat. are there any concerns about sending to much volume of raw water thru the exhaust or anything like that? All the water from the heat exchanger would be leaving thru the exhaust manifolds. Or should i at least attempt with equal length hoses to run equal amounts of raw water to each manifolds? or does that not really affect anything?

30W engine oil only in the 280 s/p.
It need not be detergent oil.

Heavy gear oil may damage the slinger pump impeller drive pins.
If it had heavy gear oil in it, you will want to test the slinger
does this need to be a marine oil of some kind? or just a 30w engine oil?

Ouch! These bolts thread into thread inserts.
DO NOT chase the threads with a thread cutting tap!
In the future, use propane torch heat on the female threaded areas before attempting to remove any fasten
since i damaged this during removal (i used a heat gun but i dont think any antisieze was used last time it was installed) should i just get a new transom plate? my exhaust manifolds are solid one piece affairs not the ones pictured in your reply. I also have uploaded a picture of my transom plate, just want to make sure i get the correct one. I'm also looking for info about a replacement for the hose that exits at the lower 5 oclock position of the transom plate.

When removing the transmission, be sure to inventory the shims, and make sure that they go back in as they were.
 thank you, i will be sure to do that. are these shims easy to spot on disassembly? im not familiar with where they are or what they look like.


another point i left out of my original post, the exhaust bellows had no flapper, im going to attempt to order a flapper to rivet to the tail where the exhaust exits the outdrive instead of the internal one. this is what i ordered

https://www.ebay.com/itm/New-Penta-Non-return-Valve-For-Volvo-replace-

i understand you just fashion a stainless or aluminum backing plate for the underside and pop rivet it on, i like this idea over the internal bellow flapper!





 
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OK, now that I can see your photos, you have an AQ200D or an AQ225D exhaust system
So these are not original manifolds for this engine?

Those exhaust manifolds have served their time
what is the flaw of these manifolds? if I remove freeze plugs and clean and dont see major rusting inside are they still serviceable? im not familiar with 3" Barr exhaust but a quick google brought up kits for GM motors, but at aroudn $1000 id hate to replace unless absolutely needed, at least right away

I also notice that you are missing the prop shaft ring anode
Yes i see that now too, when i took the prop off somethign just didnt seem right, like something was missing!

The ignition distributor may be an automotive unit. If so, that needs to replaced.
 that was on my list of things to look into, it has a vacuum advance which from what i understand a boat doesnt have.

The fuel filter is old school. I would replace that as well I will do that, good idea. i hadn't even made it to finding the replacement element for it!


You also have the old school belt driven Sherwood seawater pump. These often cause an owner to defer impeller maintenance.
If you replace the exhaust manifolds, you will be removing the Sherwood seawater pump mounting bracket.
This allows the use of the much better Johnson F5B-9 crankshaft pump.
Haha yes i noticed during removal that this was quite a chore and in no way conducive to frequent inspection or replacement...but no harder than an outboard i suppose. Im not familiar with mounting these crank driven pulleys, i will look into that. do you have to fabricate some sort of bracket for it? or does it just spin on the end of the crank and the hoses hold it?


 
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mrnkc130 said:
Thank you so much RicardoMarine! I added some pictures probably while you were responding. I apologize for my lack of posting technical knowledge. i could only seem to post 1 picture at a time and as a new reply each time.

Use caution when converting a previously Raw Water Cooled engine over to a Closed Cooling System.
Rust scale is you enemy, and may build up in the lower section of the Heat Exchanger's tube bundle
I had planned on cleaning the engine and intake as thoroughly as possible once out of the boat, hopefully that will remove a good portion of that, but perhaps i'll add a strainer or something, good point.
Rust scale within the cooling jackets is very difficult to arrest.
Best you can do, would be to remove the HE after 20 hours or so, then flush it out and dump the contents into a clean white 5 gallon bucket.
Do the same in another 20 hours or so, until you no longer see much scale.


I did notice alot of scale on the water jackets of the heard etc, this was (atleast for the last 15 years) a fresh water boat. are there any concerns about sending to much volume of raw water thru the exhaust or anything like that? All the water from the heat exchanger would be leaving thru the exhaust manifolds.
Correct!

Or should i at least attempt with equal length hoses to run equal amounts of raw water to each manifolds? or does that not really affect anything?
The T-stat housing should send an equal amount of "spent" seawater to each manifold.

30W engine oil only in the 280 s/p.
It need not be detergent oil.

Heavy gear oil may damage the slinger pump impeller drive pins.
If it had heavy gear oil in it, you will want to test the slinger
does this need to be a marine oil of some kind? or just a 30w engine oil?
As said.... 30W engine oil.

Ouch! These bolts thread into thread inserts.
DO NOT chase the threads with a thread cutting tap!
In the future, use propane torch heat on the female threaded areas before attempting to remove any fasten
since i damaged this during removal (i used a heat gun but i dont think any antisieze was used last time it was installed) should i just get a new transom plate? my exhaust manifolds are solid one piece affairs not the ones pictured in your reply.
Correct! See my previous post.

I also have uploaded a picture of my transom plate, just want to make sure i get the correct one. I'm also looking for info about a replacement for the hose that exits at the lower 5 oclock position of the transom plate.
That is a single exhaust relief "Rubber Hook".

When removing the transmission, be sure to inventory the shims, and make sure that they go back in as they were.
 thank you, i will be sure to do that. are these shims easy to spot on disassembly? im not familiar with where they are or what they look like.
Oil film may hold them to either surface. Look closely.


another point i left out of my original post, the exhaust bellows had no flapper,
That is what you want... no internal flapper.
AQ series exhaust bellows rarely go bad. In most cases, there is no need to replace it.

im going to attempt to order a flapper to rivet to the tail where the exhaust exits the outdrive instead of the internal one. this is what i ordered

https://www.ebay.com/itm/New-Penta-...108529?hash=item1ef4626731:g:rU8AAOSwF8BcYTN0

That is cheap. I have sold them for $60 with the SS backer plates.
Don't forget that you'll need to two SS backer plates and SS rivets.
Also, this will be a retro fit. Do a search for one of my posts regarding retro fitting a 290 exhaust flapper onto a 280.
There will be a portion of the 280 aluminum outlet area that needs to be ground away.

fetch


i understand you just fashion a stainless or aluminum backing plate for the underside and pop rivet it on,
You will use the OEM 290 stern drive SS backing plates.

i like this idea over the internal bellow flapper!
Yes, much less restrictive.
Click to expand...


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would this be the correct transom shield for my application?
Click to expand...

If you have this style exhaust Y-pipe, yes.

20181127_172528_wm_2048x.jpg





If you have access to a shop with an EDM (electric discharge machining), you may want to see if they can extract the broken bolt fragment.



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actually yes it does have that pipe, thank you very much for your time and help. You are very knowledgeable and helpful, I appreciate it greatly!
 
RicardoMarine said:
No! It was a joke in hopes of you having a sense of humor.
Click to expand...

I do, I guess it just went over my head, im new to this forum and im at work going back and forth. Just in the zone getting everything lined up for getting this boat back on the water!

Ive seen you in some posts say you have some obscure or obsolete parts for sale, do you have a shop or something on the web to do with these old motors and outdrives? Or just a hobby for you?

I was looking for distributors, the only reasonably priced one i see is the petronix units, im slighly familiar with petronix from hei retrofits for my 46 chevy truck. Any issues with those you are aware of? I m fairly certain the distributor in the boat is an auto unit from the vacuum advance. I see it needs to be calibrated for timing curve, do you know what that is on this motor? or where i could find a manual for this 255a? I assume its different from an auto smallblock.

And I do sincerely appreciate your help!
 
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mrnkc130 said:
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Ive seen you in some posts say you have some obscure or obsolete parts for sale,
Well, I've not used the terms obscure or obsolete.
The AQ series ran into 1996 for the gasoline engines, and into 2000 for the diesel engines.
But yes..... I still have a few of the AQ series parts.
I will eventually purge myself of them.

do you have a shop or something on the web to do with these old Engines and outdrives? Or just a hobby for you?
I spent 24 years doing AQ series service work as a small one man show, along side of being a GC and rental property owner.
I have since retired from the AQ series work and acting GC.

I was looking for distributors, the only reasonably priced one i see is the petronix units, im slighly familiar with petronix from hei retrofits for my 46 chevy truck. Any issues with those you are aware of?
I am not a fan of the Pertonix, either in the retro-fit kit or their complete units.
Pertronix uses Hall Effect triggering via a small magnet imbedded triggering wheel. They have admitted to errors of 1 to 1.5 degrees.
You can do better.
Mallory's mechanically advancing system using VR is tried and proven.
Or you can go with EST, of which I am not a fan of either.

Just make sure that the it's a marine unit, and that the curve is correct for your SBC Engine, and that you set the advance correctly.

I m fairly certain the distributor in the boat is an auto unit from the vacuum advance.
That's what it looked like to me.

I see it needs to be calibrated for timing curve,
Even if re-calibrated, due to the vacuum advance unit, it will not be "ignition source protected". Plus, the marine gasser can't take advantage of vacuum advance.
It could also get you a citation if you were to be inspected.

do you know what that is on this Engine?
Not following you on that one.

or where i could find a manual for this 255a? I assume its different from an auto small block.
Cylinder block, heads, etc are based on the automotive SBC engine.
The camshaft profile will be marine specific.

And I do sincerely appreciate your help!
You are very welcome.
Click to expand...
 
I was looking for distributors, the only reasonably priced one i see is the petronix units, im slighly familiar with petronix from hei retrofits for my 46 chevy truck. Any issues with those you are aware of?
I am not a fan of the Pertonix, either in the retro-fit kit or their complete units.
Pertronix uses Hall Effect triggering via a small magnet imbedded triggering wheel. They have admitted to errors of 1 to 1.5 degrees.
You can do better.
Mallory's mechanically advancing system using VR is tried and proven.
Or you can go with EST, of which I am not a fan of either.

They are 1/2 the price though, i think i'll stick with the auto distributor for now and just run with the engine cover off until next summer and replace before putting it in the water or running with engine lid in place.

do you know what that is on this Engine?
Not following you on that on
I was inquiring to the timing curve for this motor, I think the advance may be written on the valve covers, something like 8 degrees only, but i dont have them in front of me

I have all winter to get this boat ready, although in Texas we can start getting back on the water pretty comfortably in march or april. I hadnt planned on removing this engine but at least now it will have been all gone thru and i should know it backwards and forwards by the time its back together.

Im sure i'll have more questions in the future!
 
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mrnkc130 said:
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They are 1/2 the price though, i think i'll stick with the auto distributor for now
Not a good choice.
do you know what that is on this Engine?
Not following you on that on
I was inquiring to the timing curve for this motor,
You'll need to look it up. I'm reluctant to post an advance curve due to misinterpretation etc.

I think the advance may be written on the valve covers, something like 8 degrees only, but i dont have them in front of me
That would be BASE advance ONLY.
You'll want to see the Progressive and Total advance specs for you engine, and compare that to what the automotive distributor offers.
It will not be correct!

Click to expand...
 
Just an update if you were curios. I have the engine and outdrive and shield removed, nothing left in the boat but a outdrive size hole.

I ordered a used transom shield and have swapped all the parts over along with the steering tiller, boy that was a chore. once cleaned and greased though it went back together easily enough. transom shield seal looks to be in good shape and will be reused, it also had rubber seals around all the thru transom bolts. I'll probably just use 3m 5200 when i reinstall it all as well.

I have a 2 bearing PDS that was a PITA to get apart..bearings were pretty bad and i have replacements ordered, water intrusion somehow. I dont understand why there was a hole for a grease fitting at the top of the housing, but no grease zerc, maybe it just broke im not sure. Whats the greasing procedure for this? just pack bearings with grease on installation and put a grease zirc on the housins and give it a few pumps every once and a while?

i need to refiberglass a bit around the motor mounts, other than that not rot in transom or anywhere else.

Motor is completely disassembled. everything looks good for just cleaning up, rering after a light hone and new bearings since im in there. I'll just reassemble and check tolerances with plastigauge and hope for the best on it.

My sherwood pump had alot of corrosion on the inside and i couldnt even figure how to get it completely apart, so i'll switch tot he crank mounted pump since it needed to be replaced anyways.

cleaned and replaced grease and o rings on tilt motor, hopefully the electric parts works.

Hopefull that i'll be putting everything back together in a few weeks.
 
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mrnkc130 said:
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I ordered a used transom shield and have swapped all the parts over along with the steering tiller, boy that was a chore.
That would be the collar steering fork and spindle arm.
Make sure that you indexed the two splined areas correctly. If not, your steering stops will be OFF.

once cleaned and greased though it went back together easily enough.

transom shield seal looks to be in good shape and will be reused, it also had rubber seals around all the thru transom bolts.
Those would be the carriage bolt shank seals.
They become compressed into the chamfered bolt bores as to seal the bolt shanks. They are necessary!
Unfortunately, they are an OEM item only and are expensive.

I'll probably just use 3m 5200 when i reinstall it all as well.
See above.

I have a 2 bearing PDS that was a PITA to get apart..bearings were pretty bad and i have replacements ordered,
These are industry standard bearings/seals.
A 6206 and a 6007 with two 35 X 62 X 7mm Timken or TCM seals.

I dont understand why there was a hole for a grease fitting at the top of the housing, but no grease zerc, maybe it just broke im not sure.
The early Flywheel Covers used a grease cap. Fill the cap and thread it back on..... very slow and very ineffective.
Later ones went to a zerk fitting.

Suggestion:
Run an 1/8" Tapered Pipe Thread tap into the hole about 2/3 of the way in.
Clean the debris out.
shopping


Pick up an 18" grease gun extension hose (about $7) and thread it into the NEW 1/8" TP threads.
Fit a zerk into the other end of the hose.
flywheel cover grease hose.jpg

Whats the greasing procedure for this? just pack bearings with grease on installation and put a grease zirc on the housins and give it a few pumps every once and a while?
Re-install the PDS and new bearings.
Glue and stake the FWD seal in place.
Start pumping the grease cavity full of High Pressure grease while spinning the PDS.
This is to purge any air from within the cavity.
Install the AFT seal ONLY after you have seen grease exit the ball cage.
The AFT seal installs in the Non-Conventional direction.



Engine is completely disassembled. everything looks good for just cleaning up, rering after a light hone and new bearings since im in there. I'll just reassemble and check tolerances with plastigauge and hope for the best on it.

My sherwood pump had alot of corrosion on the inside and i couldnt even figure how to get it completely apart, so i'll switch tot he crank mounted pump since it needed to be replaced anyways.
If you had the belt driven Shewood seawater pump, you will want to remove the bracket.
This also means that you will need the Barr alternator mount.
NOTE: some must be shortened a bit.
Barr universal alternator bracket CHV 27-0083.jpg


cleaned and replaced grease and o rings on tilt motor, hopefully the electric parts works.
Caution: DO NOT try to operate the motor without the black relay control box and the upper micro switch in place and working!
Wrong move can break the cast iron clutch component.

Hopefull that i'll be putting everything back together in a few weeks.
At that time, do a search for my posts regarding the one-time triangulation alignment procedure.
Click to expand...
 
Just an update, still working on this project. With new bearings, rings, gaskets and unfortunately a new intake (cracked the cast iron one) this motor is up and running again! New fuel pump, water pump and starter (never tested and found out it was bad when i first attempted to start, luckily Autozone has a cheap marine duralast starter) after i got it up and running i ordered a replacement HEI marine dizzy and installed. Motor fires and the first turn even with no choke and 45 degree weather, compression was good on all cylinders.
I added an ebay heat exchanger which required some modification (finding fittings for this proved to be the most difficult task) and a bypass coolant filter system.
So far i still have the old style manifolds, and have converted to the johnson crank mounted pump.

Hoping to put it back in the boat in a month or two after i finish replacing some rotten stringers (started with a rotten motor mount and followed it all the way up to the helm!!) I dont think i'll be putting any floatation back in this boat since i'll justbe using it on the lake.

Its been a fun project, a little more expensive than i had anticipated but i know this boat inside and out now and it should be good for another 40 years of use when im finished.
 
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