Experience and opinions on Cat 3208 engine.

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boatdriver

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New Mexico
Hi all,

I'm a intermittent boat owner/live aboard for quite a long time. Mostly, but not all, sailboats. Now looking at buying a displacement or semi-displacement boat for cruising. I see a lot of 90's boats, particularly the Grand Banks, that use the Cat 3208 engine. I read that this engine was discontinued due to it's fuel consumption and emissions [1]. Does anyone on the forum has experience with this engine, or have you heard reports of long term problems? Any reports on fuel consumption at displacement speeds? So many boats have this engine it's difficult to believe it could be too bad of a problem.

Thanks,
BD
 
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I had 3208 naturals in the previous boat. 1983 vintage with 4000 hrs. Great engines. Smooth. Powerful. The fuel burn is determined by how hard you push them. In the vintage you're looking at they will likely be turbo, probably aftercooled as well. With any engine previous owner's maintenance and how the engines were run is very important.
 
We have had 4 boats with 3208's; a 42 GB, 46 GB, and a 50' Fleming, all with 3208N's (naturally aspirated, 210 HP.) And a second 46 GB with 3208 TA's (375 HP, turbo/after-cooled.) All were twins,model years 1986-1989. In all cases we got +/- 5.5 GPH at 8-8.5 knots, and +/- 10 GPH at 10 knots, just lower RPM with TA's. Top speed on the N boats was approx. 11.5 Knots. The 46 with TA's did over 16 knots on sea trial, over 40 GPH! Never went over 10 knots again. The downside is that they are huge, wide engines. I always wished that we had 5.9 Cummins instead, also 210 HP, but much narrower. The upside is that they were dead reliable and always started right up. For some reason the pair in the Fleming smoked like crazy when cold, but cleared up immediately under load. The other 3 did not have that issue. I always bought Cat fuel and oil filters at the dealer, but equivalent filters exist for less in most popular brands. The few other parts I needed (zincs, o-rings, etc.) were always readily available at the dealer also. I understand that some more major parts are now harder to get, but no personal experience. Very under-stressed in these applications, guessing that they would last a looong time. Ours were in the 300-4500 hour range. YMMV and good luck!
Regards,
Scott
 
I have run three different boats powered by 3208s, two with twins and one with a single. All were the 210 hp NA (naturally aspirated) version, and all were smooth, reliable engines. If they didn't come to life at the first touch of the starter, I knew instantly that something was wrong. I did not find them particularly thirsty under normal conditions, but it's true that newer electronically-controlled diesels are more frugal on fuel while getting equal or greater horsepower out of fewer cylinders.

The 3208s are wider than inline sixes, meaning they take up more space in your engine compartment and leave less space for you or your mechanic to work around them. The NA version is less of a problem in this respect, partly because there are fewer peripherals hanging off of them and partly because they require less maintenance than the TA (turbocharged and aftercooled) versions. The TAs have a lot of hardware bolted on especially around the rear of the engine, and you'll be spending some time there because the aftercoolers tend to be unforgiving of neglect.

Overall, I'd be comfortable buying a boat with 3208 NAs again, assuming their history checks out. The maintenance requirements of the 3208 TAs have always made me wary, though. I agree with Scott in Post #3 above that, all else being equal, I'd prefer an inline six like the Cummins 5.9 just for ease of access - especially in an engine compartment with twins. The difference in smoothness between the CAT V-8 and the Cummins six is negligible, IMO.
 
Every engine has its strengths and weaknesses. With 3208’s everything is good up to 375 HP. Now a 425 HP engine that spends its life in a displacement boat running 10kts or less is still a good engine.

I would however, be concerned if I was looking at a sport fisher with a pair of 425HP 3208 Cat engines.
 
Welcome aboard. Agree with all of the above. Good engine if not TA and run hard.
 
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One thing to consider is that the 3208 is not sleeved so to rebuild them if ever necessary you need to either buy a new block and rebuild or remove the block and bore them. They can't be rebuilt in place like a sleeved engine
 
I have two 3208 naturals in a 49 Grand Banks which has a stand up engine room. My previous vessels had a cat 3406TA and a GM 671. I do 8 knots at 1750 rpm's and I have had no issues. Caterpillar has a robust dealer network which makes it easier to find competent mechanics and parts. The stand up engine room makes maintenance enjoyable. I would recommend the naturals not turbo
 
One thing I should also mention is a I had a cat dealer can run my engine serial numbers before purchase and it listed where they were originally purchased and installed and any work done on them by a cat dealer. I found that info very helpful.
 
The 3208 is generally a good engine. And as mentioned, I've never seen one that didn't start pretty much just by looking at the key. However, they're physically very large and heavy for their power output. And many of the ones I've seen will throw a pretty decent haze out of the exhaust when started cold, but they clear up once they're under load for a minute and get a little heat into them.
 
Our 3208 natural has 5000 hours and still runs like a champ. Before boatdiesel.com went away, I asked the gurus how long a natural should last. The consensus was 10000+ hours with proper maintenance.
 
Yes the 3208s are wide engines. Another big difference is the Cat 3208 is a 10 liter engine, the Cummins 5.9 is, well, 5.9 liters. While the 3208 natural and the Cummins are both rated at 210 the Cummins does it with a turbo charger. Previous boat had 3208s, current boat has Cummins. Previous boat had room for 3208s, current boat does not. Both good engines. With regard to the engines only if I had the room my choice would be the 3208. More iron, no turbo.

The 3208 does have one drawback. It's very difficult to fit a bigger alternator. The available space is too small and the drive is a single vee belt. The stock alternator is 55 AMP. The Cummins can accommodate lager alternators. More room and a serpentine belt. My Cummins have 90 AMP alts. That's a big difference with today's electrical demands.

Another consideration is servicing the cooling system. The 3208 expansion tank with it's tube bundle is a challenge to remove and reinstall. Not always necessary, depending upon many variables the tube bundle can be removed with the expansion tank in place. The Cummins with it's bolt on heat exchanger is much easier to work on.

As with all older engines, OP is considering boats built in the 90s, parts and service are a consideration. In my area Cat and Cummins are both well supported. Experienced mechanics backed by good parts availability.
 
Thanks so much everyone. That's a great survey on experience with the 3208. Appreciate it a lot.

But, please don't stop if you have more to say.

BD
 
This is not helpful or relevant, but, I hate to waste a good story, so...
I was an earthwork contractor for 38 years. All of my machinery was John Deere. In 1999 I bought a new bulldozer, and the dealer sent my salesman and I to the JD factory for "gold key delivery." We were having dinner with some factory folks, and I said, "I have an ad campaign idea for you. Picture a magazine ad, the page is split diagonally, "John Deere at work/John Deere at play." A picture of me with my fleet of Deere equipment, a picture of me with my Deere 6068 marine engines in my boat. The only problem is, my boat has brand C motors from up the road... so as soon as you ship me a pair, I will install and send you the photos!" 26 years later. I'm still waiting. :-( Happy new Year to all.
Regards,
Scott
 
I have owned three boats with twin 3208's. The 210hp N are very sturdy. The turboed versions up to 375 are reliable. The high-performance 425 HP TA version can self-destruct; one common cause is any failure in the cooling system. It is true that the liners can't be replaced.But 3208's don't deserve to be called "popcorn" engines. I had one bored at a reasonable price. Fortunately I was in S Fl where there are people familiar with the Cats.
As I understand it, the engines couldn't meet the stricter emission standards.
 
Yes the 3208s are wide engines. Another big difference is the Cat 3208 is a 10 liter engine, the Cummins 5.9 is, well, 5.9 liters. While the 3208 natural and the Cummins are both rated at 210 the Cummins does it with a turbo charger. Previous boat had 3208s, current boat has Cummins. Previous boat had room for 3208s, current boat does not. Both good engines. With regard to the engines only if I had the room my choice would be the 3208. More iron, no turbo.

The 3208 does have one drawback. It's very difficult to fit a bigger alternator. The available space is too small and the drive is a single vee belt. The stock alternator is 55 AMP. The Cummins can accommodate lager alternators. More room and a serpentine belt. My Cummins have 90 AMP alts. That's a big difference with today's electrical demands.

Another consideration is servicing the cooling system. The 3208 expansion tank with it's tube bundle is a challenge to remove and reinstall. Not always necessary, depending upon many variables the tube bundle can be removed with the expansion tank in place. The Cummins with it's bolt on heat exchanger is much easier to work on.

As with all older engines, OP is considering boats built in the 90s, parts and service are a consideration. In my area Cat and Cummins are both well supported. Experienced mechanics backed by good parts availability.
We have 3208 TA's. When we put on the bow and stern thrusters and upgraded the windlass, and added this and that.... We (ok, the marina where all our work is completed) installed 120 amp Balmar 621 alternators. We had to grind down the head of one of the mounting bolts, but we got them in.
 
I currently have 2 3208TA's in my 1988 48' Chris Craft with about 3200 hours AND a 3208TA in my 1989 Bluebird Wanderlodge Bus/RV. I don't push the boat hard, 1500-1800 RPM's max. Still able to get parts from my local Cat dealer. Simple to work on, no computer/electronics to mess with. And, as others have said, they start with just a bump of the key. Boat is currently in Vermont - most of it's life was spent in FL, several trips to the Bahamas and I even shipped to Mexico (Ensenada) and kept it in San Diego for a while, then shipped it back to the East Coast. Anyway, the Cat's are low simple/maintenance, but to be fair, the only other Marine engines I've had were Gas.
 
I have twin 3208TA 435hp installed in 1996 in a coastal cruiser. I bought with 1100 hours and added 700 over five years to date. They always start, run clean after warm up, use half quart of oil per year, and if you take care of your cooling system components and regular maintenance, they are trouble free. I upgraded alternators to 100amp after some modifications mentioned above. Not mentioned above is a specific cooling weakness that is the transmission cooler - it can clog with deposits and overheat the entire engine. Regular after cooler and trans cooler maintenance is a small price for going 20kts when you want to make up time. Recommend installing EGT sensors.
 
Hi all,

I'm a intermittent boat owner/live aboard for quite a long time. Mostly, but not all, sailboats. Now looking at buying a displacement or semi-displacement boat for cruising. I see a lot of 90's boats, particularly the Grand Banks, that use the Cat 3208 engine. I read that this engine was discontinued due to it's fuel consumption and emissions [1]. Does anyone on the forum has experience with this engine, or have you heard reports of long term problems? Any reports on fuel consumption at displacement speeds? So many boats have this engine it's difficult to believe it could be too bad of a problem.

Thanks,
BD
I had a Wilbur trawler with twin 375 3208s. I learned some things the hard way. CAT determines age by gallons of fuel not hours. If run hard they may be “ older” than they appear. They can burn a lot of oil as they age.
If they don’t hit 2800 RPM at WOT something is wrong! The CAT technician attributed a low RPM to a weak turbo boost. It turned out the engines were overpropped. So for any given RPM too much fuel was being pumped. This led to a broken injector line. This lead to fuel in the sump. This lead to a runaway diesel! Scary stuff. Had engines rebuilt. Buyer beware.
 
I had a 3208NA running in my commercial troller. It powered the vessel and my refrigeration. During the season it ran 24/7 only shutting down for checks and servicing. They are rated for 30,000 US gallons of fuel through them before rebuild IF properly serviced. As stated they are a big engine taking up lots of room. And negative in my vessel was space to run larger alternators. Loved the engine though.

I had it rebuilt at a reasonable dollar. New, non-Cat pistons and rings (extra ring over stock). What a difference on oil consumption. Ran extremely clean. Next to nothing in oil burn! If I had the room I wouldn't think twice about having a 3208NA but I would want the after market pistons with the extra rings.
 
Hi all,

I'm a intermittent boat owner/live aboard for quite a long time. Mostly, but not all, sailboats. Now looking at buying a displacement or semi-displacement boat for cruising. I see a lot of 90's boats, particularly the Grand Banks, that use the Cat 3208 engine. I read that this engine was discontinued due to it's fuel consumption and emissions [1]. Does anyone on the forum has experience with this engine, or have you heard reports of long term problems? Any reports on fuel consumption at displacement speeds? So many boats have this engine it's difficult to believe it could be too bad of a problem.

Thanks,
BD
I have heard/agreed that every used boat is a compromise of what you would like to have. I wanted a Grand Banks 42 with a straight 6. I saw a GB42 for sale with rebuilt 3208TA's with just over 300hrs. I would have liked to have the more common 375HP but it was the 435HP. They passed the survey. I like what I have after 4 years and somewhere near 900 hrs. Yes, they smoke at start up. Yes, they are big engines. You can't fit much more in a GB 42- it's tight. The aftercooler is a PITA to remove for service on the port side. The impeller is also somewhat of a challenge on port. I don't know my alternator size but it's dual belt. Yes, CAT mechs always available but I do a lot by myself, and they are reliable as can be. I do purchase CAT parts also, but I have not purchased much more than filters/belts. I cruising at 1400-1500 rpm which gets me 9-10 knots. I open it up every 4 hours or so to as much as 2400 rpm for 15 -30 minutes. At WOT 2800rpm I can hit 19 kts. I hit that once a year for no longer than 5 minutes to make sure all is well.
All in all I like this engine. What's nice is the reserve power of these big CATS. Occasionally this power is beneficial to have when weather/waves are a factor.
 
My 1987 Wilbur 34 has a 3208 turbo and it's been a great engine. It presently has about 3500 hours and I know it will outlive me. Being an old man ex-sailor and not in a hurry, I'm comfortable cruising at sailboat speeds. 1,200 rpms give me about seven knots with a 2 gph fuel burn.

Previously mentioned was the difficulty installing a larger alternator. I guess that is dependent on engine access provided by the boat's manufacturer. I had no problem upgrading to a Balmar 120 amp nor with changing belts or adjusting belt tension.
 
Hi all,

I'm a intermittent boat owner/live aboard for quite a long time. Mostly, but not all, sailboats. Now looking at buying a displacement or semi-displacement boat for cruising. I see a lot of 90's boats, particularly the Grand Banks, that use the Cat 3208 engine. I read that this engine was discontinued due to it's fuel consumption and emissions [1]. Does anyone on the forum has experience with this engine, or have you heard reports of long term problems? Any reports on fuel consumption at displacement speeds? So many boats have this engine it's difficult to believe it could be too bad of a problem.

Thanks,
BD
Here’s my short answer on 3208 Turbos. Loud, louder, whistling loud, whistling louder, and they’ll chase family and friends off the boat, possibly forever. (Which might not be a bad thing 😳)
 
I bought a Californian 35 at auction pretty cheap. She had twin 3508s in her one of them was seized. Also had fuel in the bilge.

After purchase I brought the boat around to my dock and found that it had sucked a valve on the number eight cylinder on the port engine. The engines had aftermarket turbochargers on them. When Cat builds that engine with a turbo, it uses dual valve springs. This did not have them. The previous owner was having the boat delivered to Florida and I believe the delivery skipper just throttled them up and left them close to full throttle to reduce the delivery time. Engine sucked a valve and that was it.

I put a new head and piston in her and she ran fine. (Also found a corroded hole in a fuel tank and fixed that). They were good engines and would put her on plane with a bit of effort and then throttle back and stay up. I personally liked the engines, well built, fairly easy to work on and good power to weight ratio.

Michael
 
Here’s my short answer on 3208 Turbos. Loud, louder, whistling loud, whistling louder, and they’ll chase family and friends off the boat, possibly forever. (Which might not be a bad thing 😳)
This is a problem I've never experienced. The sound emitted from the exhaust of my 3208 is deep and gives a sense of power. I like it. Never a whistle.
 
Here’s my short answer on 3208 Turbos. Loud, louder, whistling loud, whistling louder, and they’ll chase family and friends off the boat, possibly forever. (Which might not be a bad thing 😳)
That whistling noise might have been sneaking out of the air intakes, maybe around a thin or badly-seated air filter.
 
Here’s my short answer on 3208 Turbos. Loud, louder, whistling loud, whistling louder, and they’ll chase family and friends off the boat, possibly forever. (Which might not be a bad thing 😳)

This must be one person’s experience with a poorly maintained boat.

3208’s are among the quietest engines of their period and size. While modern engines and smaller engines may be quieter. Most engines of the 80’s were noisier.
 
I have run three different boats powered by 3208s, two with twins and one with a single. All were the 210 hp NA (naturally aspirated) version, and all were smooth, reliable engines. If they didn't come to life at the first touch of the starter, I knew instantly that something was wrong. I did not find them particularly thirsty under normal conditions, but it's true that newer electronically-controlled diesels are more frugal on fuel while getting equal or greater horsepower out of fewer cylinders.

The 3208s are wider than inline sixes, meaning they take up more space in your engine compartment and leave less space for you or your mechanic to work around them. The NA version is less of a problem in this respect, partly because there are fewer peripherals hanging off of them and partly because they require less maintenance than the TA (turbocharged and aftercooled) versions. The TAs have a lot of hardware bolted on especially around the rear of the engine, and you'll be spending some time there because the aftercoolers tend to be unforgiving of neglect.

Overall, I'd be comfortable buying a boat with 3208 NAs again, assuming their history checks out. The maintenance requirements of the 3208 TAs have always made me wary, though. I agree with Scott in Post #3 above that, all else being equal, I'd prefer an inline six like the Cummins 5.9 just for ease of access - especially in an engine compartment with twins. The difference in smoothness between the CAT V-8 and the Cummins six is negligible, IMO.
This must be one person’s experience with a poorly maintained boat.

3208’s are among the quietest engines of their period and size. While modern engines and smaller engines may be quieter. Most engines of the 80’s were noisier.
Not related to this original post, but I’d love to know why my twin 3208N will all of a sudden not start. Did about everything but no luck. My post is on “hale tiki”. Could it be all injectors need re-tooling? Both engines stopped exactly same time?
 
"Not related to this original post, but I’d love to know why my twin 3208N will all of a sudden not start. Did about everything but no luck. My post is on “hale tiki”. Could it be all injectors need re-tooling? Both engines stopped exactly same time?"

It may be electrical. Are your engines key start and stop? Turn the key off and they stop? In other words energize to run. That system requires power to hold the fuel solenoids open.
 
Yes the 3208s are wide engines. Another big difference is the Cat 3208 is a 10 liter engine, the Cummins 5.9 is, well, 5.9 liters. While the 3208 natural and the Cummins are both rated at 210 the Cummins does it with a turbo charger. Previous boat had 3208s, current boat has Cummins. Previous boat had room for 3208s, current boat does not. Both good engines. With regard to the engines only if I had the room my choice would be the 3208. More iron, no turbo.

The 3208 does have one drawback. It's very difficult to fit a bigger alternator. The available space is too small and the drive is a single vee belt. The stock alternator is 55 AMP. The Cummins can accommodate lager alternators. More room and a serpentine belt. My Cummins have 90 AMP alts. That's a big difference with today's electrical demands.

Another consideration is servicing the cooling system. The 3208 expansion tank with it's tube bundle is a challenge to remove and reinstall. Not always necessary, depending upon many variables the tube bundle can be removed with the expansion tank in place. The Cummins with it's bolt on heat exchanger is much easier to work on.

As with all older engines, OP is considering boats built in the 90s, parts and service are a consideration. In my area Cat and Cummins are both well supported. Experienced mechanics backed by good parts availability.
The 210hp Cummins 5.9 is not a turboed engine. The turboed and aftercooled 5.9 can run up to about 370hp. The 210hp is and natural engine.
 
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