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Need help identifying which engine / oil tube

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SoFloMerc

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Hello all! I am not having much luck identifying the exact engine that I have. Just purchased the boat, I was told it is a rebuilt 5.7 from 2006, but can't find a serial plate in the usual spots. I did find some stamped numbers on the front of the engine on the machined flat surface, lightly sanded away the paint to read them. However, they don't seem to line up with any serial numbers in the database here. Pics below.
Serial1.jpg Serial2.jpg
The reason for my search is that apparently this engine was dropped in without an oil tube or dipstick installed. I'm trying to get that right before taking it out. I know, shame on me, and I am starting to believe the previous owner's assertion of only putting 15-20 hours on this engine. After lots of sweat, light tear down, and climbing around the engine bay, I think I finally found the location for the oil tube on the port side of the engine (see pic - circled in red). It looks to be blocked with a bolt and sealed with RTV or silicone. I was expecting it to be on the starboard side based on what I thought the engine was, but after removing the starboard exhaust manifold, it wasn't there. So, I have 1 oil tube / dipstick on hand, another ordered, and I'm not really sure if either of them is right. I'm still trying to narrow this down to prevent having to break the seal on everything and not being able to return these (surprisingly expensive) parts...

OilTubePort.jpg

Any help is appreciated, thanks in advance!
 
What I found is this:
TO - Tonawanda NY plant
817-Aug 17th
CKB- 350 cu.in. '72-74 year models.
the other number 12s... came up with nothing <don't mean anything. Maybe others can find it>
Are there any numbers on the other side of top rear of the block?
 
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First, Take a pic of the entire engine showing intake, carb, valve covers and pully system.
You dont have anywhere near enough information for any help.

What year is the boat? Any serial number on outdrive (also what outdrive, Alpha or bravo) serial number of transom assembly.

When you say rebuild in 2006,
What does that mean? The original block was rebuilt? Or a rebuilt block was installed in 2006?
 
Thanks for the help so far! Here's a pic that I have readily available, with an engine cover that I don't believe is correct, maybe the original from 2000 (and no numbers on that cover). Also, a blurry screen grab with the cover off, but can't see the carb... I'll take some better pics when I can get back to it.
Engine_orig_1.jpg Cover_off.jpg
Top rear of the block has "GM 3970014" on the port side, which Google says is 350 SBC. Some smaller letter groupings on the other side "T 28 00NV", I'll have to take pics of those if it helps.

As far as more boat / engine details - 2000 Sea Ray Sundeck 240. 2006 is the year engine that the previous owner says was rebuilt and installed to replace the original 2000 engine. I took that to mean a 2006 engine that was recently rebuilt? The numbers may not support that. By replaced, that means everything - engine, oil pan, pulleys, hoses, accessories, everything from 2000 was pulled out as a single piece and the fully-built replacement dropped in, 3 months ago. Outdrive is original Bravo from 2000, again hard to find details on that either - no serial plates, everything on the aft end has a healthy layer of bottom paint.

Any additional specific pic requests and I'll be on it!
 
1. V belts tell me 1990's vintage block.
2. Count intake bolts. 87-95 will have 12. 96 and up vortec will have 6 or 8 I forget.
3. Take flame arrestor off and pic of carb please

But based on your pictures I will look and see what I can come up with on this sites parts pages.
 
OK, Based on what I can see in the photos, and based on V belts being used it may be a 87-95 block.

the oil dip stick and tube goes on the STARTER side of engine and if there is a plugged hole there then this link is to the parts that may be what you need. Items 18, 19, 20 and 21.

I am not 100% sure but this may be what you need. Link below. It gives part numbers and cost if you purchase thru this web site.

 
Also I dont believe the big cover over the carburetor came with the replaced engine. It may have been on the original engine. It looks like you have a carburetor and possibly a thunderbolt ignition. Take a good pic of the distributor cap and wires also
 
Great feedback, going out to take carb and intake pics now. Just to clarify, the first block pic that I took (above) is on the port side of the engine (non-starter side) and it shows what I believe to be the dip tube hole and "boss" in the block for that. That similar location on the starter-side just has a threaded plug and no "boss". I took the starter-side exhaust manifold off already and this is what I see there (threaded plug circled), and a zoom out:

starter-side-plug.JPG starter-side-out.jpg

There's not much going on that side of the block between the engine mounts.
 
Your original pic of tube location, you should have pulled the plug wire...for better view.
The last pic of the starter side is not very good and its hard to tell what thd pic shows.

Count the intake manifold bolts. And a clear pic of carburetor
 
I'm inclined to think its an older two piece rear main seal block...probably made in 1980 or newer, based on the limited data I have collected and filtered over the years...
 
Ok, If the oil dip stick tube is on the Port side, Below are two links covering 1978-1986 350 V8 engines with dipstick on port side.

I hope they did not break it off and part of the tube is stuck in the hole.

anyway, below are the two links clearly labeled for the years. for engine years older (a few years only) the same images are shown at the 1978-1982 link.

GM 350 1978 thru 1982 Link: https://www.marineengine.com/parts/...982/4908850-thru-6218461/oil-pan-and-oil-pump

Gm 350 1982-1986 link: https://www.marineengine.com/parts/...86/6218462-thru-0b525981/oil-pan-and-oil-pump
 
makomark said:
I'm inclined to think its an older two piece rear main seal block...probably made in 1980 or newer, based on the limited data I have collected and filtered over the years...
Click to expand...
I agree, Everything I have looked at 1987 and newer, the dip stick is on the starter side of engine. At least what is shown on this site. It does not go up to current dates. It seems to stop at 2000-2001 for most engines.
 
I'll go further and say I can't find any 'matches' with the engine ID code and the Factory service data on same...so it's highly likely not an original Mercruiser build block....

If the intent is to use a block mounted dipstick, make sure the oil pan used is a "match" otherwise you'll be pulling your hair out trying to make sense of the markings...
 
I am pulling the port-side exhaust manifold tonight, stay tuned for better pics of that side. In the meantime, here are some pics of the top end, with carburetor, distributor. I count 12 bolts on the intake manifold.

Carb_top.JPG Distrib_top.JPG Distrib_side.JPG

I don't know that I've paid any attention to the rear main seal, I'll try to capture that in pics as well. And yes, I am trying to end up (eventually) with a block mounted dipstick, matching whatever engine / oil pan this is...good point on all of that being a match. Back at it!
 
Well,
1. Center bolt valve covers mean heads are 1987 and newer.

2. That is a Rochester Quadrajet 4 bbl carb

3. That is a Thunderbolt ignition. Not sure if it is IV or V.

1987 and newer engines (original builds) with center bolt valve covers were all one piece rear main seal engines. Also the dip stick would be on the starter side.

One more thing to let us know about.
The intake manifold has 12 bolts.
The four center bolts, two per side.
Are they on a different angle then all rhe others? 87-95 heads the four center intake manifold bolts were vertical and the remaining 8 are angled. Let us know.

Your engine may be a mix and match of parts frim different years
 
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Thanks again for all the feedback! I will take a closer look at those manifold bolts tomorrow and note the orientation. I am at a stopping point for the evening, but I have some more pics to post. For the rear main seal, I took a pic of the port side flange bolt, it is the same on the other side, does this indicate the 2-piece, or do I need to view it head-on to look for a horizontal split there? The pic is top-down.
rear_seal.jpg

For the port-side block, I took some pics after removing the exhaust manifold, exposing what I believe is the oil tube port. The bolt was still sealed with gray rtv / silicone in the pics, after I scraped that away, there is a 12-point bolt head there, didn't have 12-points in my tool bag so I'll have to pull that tomorrow to see what adventure it hides.
oil_port_top.jpg
On the side of that location there is a threaded opening, I haven't verified if that connects to the tube flare or if it is shallow for mounting something, maybe the clip from the remote oil filter hoses that I circled in green? That clip was not bolted to anything when I removed the exhaust manifold. I put red arrows on the bolt head and threaded opening in the pics.
oil_port_side.jpg oil_port_side_arrows.jpg

On a positive note, the oil pan looks to match this same tube location with its own smaller flare out at the same position. Maybe that indicates the pan matches the block?? Fingers crossed...

I would not be surprised if this is a Frankenstein of an engine, I think I expect that at this point. More tomorrow!
 
They are talking about crankshaft rear main seal. Entirely different block, crank & pan from earlier 2 piece to later 1 piece design.

Your photo is of the rear engine mount area. Has nothing to do with determining vintage of engine block.
 
I see, thanks, still learning. From the exploded views, the rear seal looks to be inside the flywheel housing, so no way to visually verify without a true teardown.
 
SoFloMerc said:
I see, thanks, still learning. From the exploded views, the rear seal looks to be inside the flywheel housing, so no way to visually verify without a true teardown.
Click to expand...
not at all...remove the flywheel cover and pop the flywheel and the 1 piece seal retainer is pretty obvious...

I think Jack go it - mixed vintage assembly...
 
Correct. But he still has the engine in the boat.

Since oil capacity is 5 qts with a new filter, just get a dipstick that fits. Empty oil, replace filter, run it 5 minutes then let it sit so all the oil can drain down. Check oil level & scribe the stick for full.

There were some engines that had the dipstick go to the drain plug. These had the hose threads at the top for the drill pump oil extractor. I'm thinking OMC used them. This would be another possible option.
 
Friday update - I genuinely appreciate all the help so far. And, I'm still interested in understanding what combination of engine parts I do have.

First a picture to answer kghost, and of course more questions... The intake manifold middle four bolts look definitely more vertical than the outer ones, not perfectly vertical to my eye, and all of the outer 8 are more angled. An outer bolt is in the foreground of the pic. Does this mean 87-95 block? Also, Thunderbolt IV vs V, can you tell by the control module that I have? I see a Denso 131800-7071.

intake_bolts.jpg

Second, Eureka! I was able to verify oil in the pan! I pulled out the 12-point bolt to find the opening below, and tested for oil with a transmission dipstick that I had on hand.

port_open.jpg oil_on_stick.jpg

When I inserted the dipstick, I could feel it touch the bottom of the pan. The insertion depth looked to be similar to the "in-pan" tube length of the 2 tubes that I have now on hand. So, is it safe to assume that I can calibrate this engine build with almost any tube / dipstick that will fit?? As Droid suggests, a drain / fill cycle should nail it, but assuming the correct oil level is in it now, that could mark the initial "full". Or, is there something more unique to the different years of oil pans and oil quantities that I would be missing here?

As far as I know, without access to the drain plug (which I don't have, and don't see a quick-drain tube down there), the only method to change the oil is through the threaded fitting on the end of the dip tube.
 
1. Intake bokts say Heads are 87-95 cast iron Small block chevy.

2. TB IV or V we would need to see a pic of what you decscibe. The TB modlues are very unique.

3. The engine block based on what I found and linked to is older than heads. What year, may be what Roadking posted earlier but still a little bit unknown.
 
I don't think I would assume anything regarding the oil quantity or for that matter the oil type currently in there.

Also, I'd try to level the boat (engine actually) prior to marking the dipstick. Understand the boat may (probably will) sit at a different attitude on the trailer and also when floating.
So I'd also consider making a note of full & add in each scenario. I really don't know if most people take that into condisrtation or not.
 
Good point Droid, had similar thoughts about on trailer (where it lives now) vs level on water. Noted. I think I have a path forward to put a dipstick tube on the engine to monitor the level at least.

Back to the ignition, and then hopefully I can leave you guys alone for a while. This module is at the end of the wiring harness that goes to the distributor, Google says this is the Ignition Control Module, but I don't see reference of whether this means Thunderbolt IV or V...

ign_module1.jpg ign_module2.JPG ign_module3.JPG

Based on the collective good feedback so far, I am believing there is not much on this engine from the 2000's but the filters. Heads 87-95, block 80's or older (?). I'm hoping at least the rebuild has been recent, but no looking back now... For the easy things to replace on the front of the engine (belts, PS pump, alternator, etc.), should those match the year range of the heads? Or is it another case of anything goes?
 
IDK, way too new for my blood. I still operate with points & condenser.

You bought yourself a Frankenboat. Engine is definitely late 80s to probably mid 90s. Like stated above, V belts vs serpentine belt. Rain guard says digital ignition & EFI. You have a carburetor & distributor with the big diameter cap.
 
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It looks like a inline 4 cylinder control module. Possibly a newer module used with a non efi engine.

But it ia NOT a Mercruiser Thunderbolt timing control module.

I will say, someone knew what they were doing, be it 100% not what should have been done. But they were smart enough to make it work.

In the pleasure boat world and especially when using a site like this to help with problems, Most if not all of us work with 99% OEM issues and what should be and how they work.

As seen we post links to the way the factory built it and use the SAME parts as listed to fix it.

You have a real bastard child...
 
There is a Mercury part number on that box. It's NLA.... no idea what it fits but I may be able to look it up when I get home.

You probably could get the old conventional distributor from late 70s/early 80s 260 hp & remove all doubt.
 
Although I dont know 100% ,
I think, these ignition timing modules dont know or care if its a 4 cyl, 6 cyl or 8 cyl engine. Its the rpm and trigger (sensor and rotor assembly under dist cap) that pulse the timing module. The only other function of the module is the timing advance max amount and the rate at which it gets there.

Its common for boaters to use V6 TB modules for advance curve changes for V8 engines....(performance seekers)
 
I'm always pushing the performance envelope at 2800 RPM....
 

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That ICM is a thunderbolt five from Merc that started in I believe it was in 1994.5… the year mentioned, Merc also had a kit that when the 4 went bad you upgraded to the 5 so anything is possible when using a ignition control module as a reference guide in situations like this….< plus, I could be wrong but the mounting hardware sort of looks different than what memory is trying to say in the moment.

An example,
www.ebay.com

Mercruiser 840130A4 THUNDERBOLT V Module 500 | eBay

840130 Thunderbolt V ignition module with knock module. No longer available from Mercruiser. I have two sets of these, this auction is for one set however.
www.ebay.com

To help maybe fine tune a search of the engine, if the numbers are available as mentioned/shown in either of the following guides, then it may help find a clue too…,
EN_08.PDF , mcsb02_08
 
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