Marine L-88 Engine w/ Cast Iron Heads
 

I picked up an engine yesterday and thought I would share. It is a complete L-88 engine that was built by GM with cast iron heads. The cast head L88 is a subject I have always been interested in. I have seen a few pop up over the years and mos message boards seem to dismiss the engines as being home built or L71/L72 engines with a 3933198 intake added.

This engine was removed from a 1969 speedboat and was the original engine to the boat. It was running 2 days ago. The suffix code is 7BL. I have seen this suffix before and always wondered what it was. The engine has the correct 3933198 intake, 840 heads, heavy duty AC fuel pump, 7/16 dimple rods, and the 7115 steel crank.

Re: Marine L-88 Engine w/ Cast Iron Heads
 

Here is the engine as it was pulled. The carb is a 3246 service dated Holley. I have seen 3246 carbs on most marine 427s. The pulleys are GM units but are not deep groove.

http://i179.photobucket.com/albums/w...lete1Small.jpg

http://i179.photobucket.com/albums/w...lete2Small.jpg

Re: Marine L-88 Engine w/ Cast Iron Heads
 

The block is a 3963512 casting with a casting date of B 5 9.

http://i179.photobucket.com/albums/w...umberSmall.jpg

http://i179.photobucket.com/albums/w...gDateSmall.jpg

The heads are both 3919840 with casting dates of A209 and C139.

http://i179.photobucket.com/albums/w...stingSmall.jpg

http://i179.photobucket.com/albums/w...Date1Small.jpg


http://i179.photobucket.com/albums/w...Date2Small.jpg

Re: Marine L-88 Engine w/ Cast Iron Heads
 

The front pad is stamped TO3177BL. The 7BL suffix must mean closed chamber L-88 with cast iron heads.

http://i179.photobucket.com/albums/w...uffixSmall.jpg

The 3933198 intake is dated 9.18.68. I believe the 198 intakes were only made in certain runs. I don't think I have ever seen a casting date from October 68-Feb 69 unless the 198 was hand stamped.

http://i179.photobucket.com/albums/w...ntakeSmall.jpg

http://i179.photobucket.com/albums/w...eDateSmall.jpg

Re: Marine L-88 Engine w/ Cast Iron Heads
 

Factory high lift rockers are still intact.

http://i179.photobucket.com/albums/w...ockerSmall.jpg

L88 pushrods still there

http://i179.photobucket.com/albums/w...alleySmall.jpg

Re: Marine L-88 Engine w/ Cast Iron Heads
 

Cool original fuel pump

http://i179.photobucket.com/albums/w...lPumpSmall.jpg

http://i179.photobucket.com/albums/w...pDateSmall.jpg

Re: Marine L-88 Engine w/ Cast Iron Heads
 

Pulling the pan was exciting. No denying this is a L-88

http://i179.photobucket.com/albums/w...emblySmall.jpg

http://i179.photobucket.com/albums/w...eRodsSmall.jpg

http://i179.photobucket.com/albums/w...CrankSmall.jpg

Re: Marine L-88 Engine w/ Cast Iron Heads
 

I decided not to pull the heads since the engine runs great and I can see it is standard bore due to the TRW pistons having GM and the part number on the undersides.

Re: Marine L-88 Engine w/ Cast Iron Heads
 

neat find. im really surprisd at the carb. most OE marine carbs have 180 degree vents. having worked at a boat dealer ive never seen one like that factory.

we had at least 4 early 70's BB chevys and fords and the carbs all looked like this

http://www.michiganmotorz.com/images...4150_LG001.jpg

Re: Marine L-88 Engine w/ Cast Iron Heads
 

----Since the carb is service dated I would guess that the owner or mechanic bought an automotive carb when the boat carb went bad. It was probably cost effective at the time, but not too safe......Bill S

Re: Marine L-88 Engine w/ Cast Iron Heads
 

I doubt it. I have had 3 marine big blocks and all 3 had 4346 carbs. I have read about others online that also had the 4346. Maybe this is before the Coast Guard required the curved bowl vents on marine applications? I wish is was a 4296 carb with a Fed or March date like the engine [img]<<GRAEMLIN_URL>>/smile.gif[/img]

Re: Marine L-88 Engine w/ Cast Iron Heads
 

Here's another that had the 4346:

http://forums.corvetteforum.com/c3-tech-...te-running.html

Re: Marine L-88 Engine w/ Cast Iron Heads
 

3246 or 4346?

Re: Marine L-88 Engine w/ Cast Iron Heads
 

OOOPS, 3246. My mind must have been elsewhere.

Re: Marine L-88 Engine w/ Cast Iron Heads
 

http://i179.photobucket.com/albums/w...6CarbSmall.jpg

Re: Marine L-88 Engine w/ Cast Iron Heads
 

So how did the boat scoot across the water? Thats the important question. Could you keep your foot in it? [img]<<GRAEMLIN_URL>>/smile.gif[/img]

Re: Marine L-88 Engine w/ Cast Iron Heads
 

...How can a marine motor be identified.... from a car motor?
What are the signs? [img]<<GRAEMLIN_URL>>/dunno.gif[/img]

Re: Marine L-88 Engine w/ Cast Iron Heads
 

I bought the engine out of the boat but never rode in the boat. It was supposed to go 60MPH. Seems pretty fast for on the water.


Jason

Re: Marine L-88 Engine w/ Cast Iron Heads
 

Many times marine motors have the plugs taken out of the front of the heads for water ports. Also, the exhaust threads are usually studded for the manifolds.


Jason

Re: Marine L-88 Engine w/ Cast Iron Heads
 

Has anyone ever seen the M/T finned covers with no logo like these ones?


Jason

Re: Marine L-88 Engine w/ Cast Iron Heads
 

I've seen them. They are very early. 1965-1966. Small block covers are the same way. They may have gone on a few more years but not sure.

-Matt

Re: Marine L-88 Engine w/ Cast Iron Heads
 

Thanks Matt


Jason