10.2Ltr G M V8's any info?

alruss

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I have been asked to look at a pair of the above, from the information I have had, it
sounds like the head gaskets have gone. Are the parts available, gaskets etc.. Many thanks in anticipation, Alan
 
Unit 18 has may be the man to talk to,he has been nursing along a pair of similar beasts for years.
Howver tonight he is parked up a local creek,so not around poss until monday.
 
I have not seen them yet, but they are in a Laguna, recently bought by a friend. He has the
manuals so model no should be avail on Monday. Thanks.
 
So probably the same lumps then... Think Unit 18 bought two removed from a Laguna in Grimsby that was being re-engined to have access to parts. Think you may have to get to the US to find parts for the engines... or you may get lucky and find the parts available through GM/Detroit Commercial network...

Got another friend in Norway with a Laguna 11.5M ... but he also re-engined with 300 hp Cummins 5.8L's... pretty sure the original ones got scrapped..

The engine's never achieved a reputation for reliability, but off the top of my head I do not remember how long they stayed in production.
 
Strange hat some research can do... as well as notebooks...

Think the engines were based on an Oldsmobile petrol engine, which was a fairly solid engine for the time..... rock solid in petrol form one may say.... When the engine was re-configured to diesel they were put in larger cars with automatic transmissions..including cadillacs.... When introduced in heavier applications however (trucks, boats etc.), it was a different story as it was not designed for heavy use/abuse..... hence reputation..

So parts may be avilable through an automotive dealer with knowledge and connections to US cars ... preferrably late 60's and into 70's...

Ask me anything about two-stroke GM / Detroits and I'll try to help .... but these ones have me stumped beyond what I have found and revealed here I am afraid.....
 
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Hello there, I got head gaskets (copper) made up as I couldn't find any a couple of years ago. I went to a local cylinder head specialist and he got the ones I'd taken off copied, very good but expensive.
As regards spares I had a lot of trouble tracking them down, in the end I was fortunate in that a forum member knew of a couple for sale which I bought as spares.
There are a couple of problems with them generally. Firstly they were designed to be N.A running at around 220ish hp, AM fiddled about with them and bolted a turbo on and they were alleged to produce 270hp....so don't run them at the top of the rev range...and they are old.
AM in their wisdom decided to run the starboard engine backwards, fitting their own cam and water pump. It also uses more fuel.
I had a problem with the injection pump, I got in touch with Ambac and they still had all the specs and parts were available if needed. Armed with this I took it to Colchester Fuel Injection and it was repaired.
So if you run them in the lower rev range I think they'll go on for a long time, very tolerant of overheating as blocks and heads are cast iron. When I took the heads off they still had the hone marks.

All the best, Al
 
GM V8 diesel engines

Much misinformation here. Divemaster is the acknowledged expert on DD strokers and is close.

#1 The original Oldmobile LM9 V8 and later 6.2 and 6.5 V8 engines were all indirect injection engines out of GM Michigan overseen by Ed Cole. The LM9 V8 would go down the Olds 370 gasoline V8 line but had no parts in common with it.
#2 The 6.2 and 6.5 are no relation to the LM9 V8. Second effort by Michigan gasoline engine guys but little better than the LM9. These engines were NEVER intended for the GM commercial truck line.

# 3 The 108x112 8.2 V8 is a totally different beast. This four stroke engine came out of the Detroit Diesel Division of GM. Unlike the pansy motors out of Michigan this is a big 720 Kg beast. Has direct injection as opposed indirect and long stroke as opposed to silly over square motors with indirect injection. The GM 8.2 was first released in 1980 for GM trucks, and then in 1981 as a 260 Hp marine motor. Shortly after came out at 300 Hp.
Forget all about the small stuff the 8.2, there was never a 10.2. Motor was never supported by Detroit Diesel and production finally ended when GM sold truck division to Volvo.

Do not mess with this motor, they bite! If head gaskets fail it is a symptom of something else wrong. Piston bore clearances were tight and a small overheat caused piston pick up. Swarf from pistons would then get everywhere inside the engine.

If you pull the heads you need correct tooling to re-set injectors, Divemaster will know what I am talking about. Some parts still available out of Federal Mogul, unless you know all about one of these, stay away.

Email me for a GM 8.2 260 spec sheet if you require more information. In fact the safest thing to do is just look at the spec sheet and nothing else.
 
Err...don't get where you're coming from, as I have a pair of DH637 (10.4 ish L) Toro-flow engines, fitted in 1972, one of which I've fitted head gaskets to and as I've said, the bores were peachy.
As for resetting the injectors...don't get you? :confused:
 
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The GMC TORO-FLOW Diesel Engine, was basically the petrol V6 & V8 engines converted to Diesel.

Do a Google on DH637 + Toroflow and you'll get some of the information ... not much around as the V8's were not made in great numbers ... the V6's ended production some time in 1974... and I think V8's two years earlier...

Engine Model Gross Horsepower
Net Horsepower
Gross Torque lbs. ft.
Net Torque lbs. ft.
Bore - Stroke
Displacement
Compression



DH637 V8 220 @ 2800 rpm
200 @ 2800 rpm
458 @ 2000 rpm
444 @ 2000 rpm
5.125" - 3.86"
637.0 cu. in.
17.5 to 1

By the way Al, think you can fit in DDV8/71's, with low profile oil pan in your 11.5 m Laguna ...... but suspect you'll make corkscrews of the shafts..., but the V6/71 at about 350 - 450 Hp could be a great (and "cheap") lump to fit in... if you ever have to replace the four DH637's you have.
 
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Wish I had the money to do that Alf, but the things just keep plodding along. As you say, the shafts on the Laguna are stupidly skinny, did your friends re shaft theirs?
PS I've got a proper workshop (photocopied) manual and the fuel pump specs for both engines if needed by anyone.
 
... Think he is running with original shafts....not sure about the gearbox ratio though...

Wonder what this guy did ... but they do not look over-sized...

http://www.boatsnz.co.nz/boatsales/...iewno=50&sort=name&hpage=&noview=&broker=tayl

Nice transom gate though ...

328988A226_1.jpg


Sorry for the drift...
 
Thanks for all this fascinating info, my mate has not come back with model numbers yet.
I have been told that the boat has not been used for some years, and when started on the
first visit, they ran perfectly, no smoke, steam or water in sump but they were not used under load.
On the second visit, first one engine, then the other started to produce steam from the breather, and signs of water in the sump when they were out under load. To me classic
symptoms of head gasket problem probably no inhibitor in the cooling water.
All this is only what I have been told, I have not seen them yet. What engines would the panel suggest as replacements? Nanni's have been mentioned as one option. Again many thanks for info.
 
Model no of engines

I now have model no of engines, DH637 I also have a maintenance manual for the truck engine, which I can scan and send if anyone needs it. Again many thanks for assistance
and info.
 
That maintenance manual is vital ... do take care of it... copy it, scan it (if you cannot scan, I'll take a copy and will scan and deliver a searchable file back). These engines are basically truck engines with marinisation kits ...plus American Marine did bolt a turbo on these onboard the laguna 10 and 11.5M, which made them somewhat more stressed.... but the manual should give you most information you require...... all you need now is the spares... ;D

Good luck!!!
 
Sorry .. missed the question of replacement engines...

"Cheap" refurbished ones, whilst maininaining intended cruising at 16 - 20 knots would include;

Detroit V6/53 Drop in..., but spares may be an issue ... all DD's people will day are "old fashioned ...but is good for 40.000 hrs plus)
Detroit V6/71
Detroit V8/71
Detroit 6/71 Low profile (Block inclined at approx 45 degrees)
Detroit 8.2L

Would personaly try to avoid DD 53 series and the four stroke 8.2L

More expensive refurbs would include;

Cummins 5.8 (300 hp...ish)
CAT's
Perkins Sabre's in the high 200 Hp range
Ford Mermaid's in the high 200 Hp range
Volvo KAD43's
Volvo KAD300

These guys have a few... ask for quotes... and you may be surprised.... (I was when I enquired about two 650's)..

http://www.goldcoastpower.com/product_engine.cfm

Of course if you change your operating parameters, or would consider new engines ... then the world opens quite widely from Deutz, Vetus and Iveco's to Steyrs and MTU's... depending on how deep your pockets are...
 
I would say if your friend has the money to re-engine and is going to keep the boat for a considerable time then that's the way to go, get a professional to give you some options. There's not a lot of room between the hull and the saloon floor. The spindly shafts may limit what you can fit as well, from memory the gearboxes on the 10.4's run 1.5.1.
Please remember you will probably never get your money back if you do all this.

It may be worth finding out what is wrong with the engines you've got in there. They do breathe a bit heavily out of the top...after all they are big crude old lumps, the hoses out of mine needed re routing as the condensation used to puddle in them due to the tortuous path. There's several little tweeks that I've had to do .
What oil pressure are you getting...what temp is the water/oil etc, at what revs do you use it?
It may be worth persevering with the 637's for a while, you don't say if your friends experienced with boats...to replace the engines is a big step and needs some serious equipment to remove them. I was told they weigh almost a ton each!
I'm more than happy to pop over to have a quick look at them for you as long as its not a silly distance from me (Kent) or PM me and I'll give you my phone number.
Regards, Al.

PS..
" I now have model no of engines, DH637 I also have a maintenance manual for the truck engine, which I can scan and send if anyone needs it. Again many thanks for assistance"

Just remember the Starboard one runs backwards!
 
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Total fred drift here I know, but I saw this ad in a newsletter today, and thought that Alf might be interested....

Very nice....but V12/149's means that each cylinder is 149 cubic inch ... (that is 2.44L) giving these a displacement of nearly 30L ..... which is probably a tad too big for the Laguna...

If you'd want something "hot" in the Laguna (or mine) in a "small" package, you'd find a couple of recon V8/71, install large twin turbo's and Military Spec Injectors ....., set governor up to 2600 RPM and get about 650 something Hp... (I can change the ratings on my straight 6/71 to about 485hp change injectors and turbo) ... more space and you'd fit in the V8/92 series and get about 900 Hp ....
 
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