The elusive 224/3.7 MerCruiser banger

you can make the tool. look in the early posts for that.

 

Is there a source for the o rings that seal the tube to the oil pump? Specifically, the square cross section ones.

 

Sean, there is good reason to assume that delco distributors of that era will have parts that will interchange with the mercruiser distributors. HEI distributors are too wide, however as the shaft angles into the engine, placing the distributor body much higher will give the needed room. There was a photo of that arrangement posted here (by Randy ?) years ago.

4 cylinder hei distributors are not huge like the 8 cylinder ones, but their diameter is somewhat greater than stock non-hei ones so the change is possible without huge modifications, it will need a little more space beneath it to gain diameter clearance and the body is also somewhat taller than the original mercruiser distributor body.

 

You realize that Big Chief's post was in 2008, right?

Beck made a tool, see this link:

https://www.jalopyjournal.com/forum...ercruiser-banger.256713/page-78#post-13861675

 

possibly mcmaster.com they are a industrial supply house that offer square orings. I havent completely disassembled my engine yet but will try to get some dimensions of the oring or where it fits and verify a part number with mcmaster.com .

 

I loked at some pics of the vega distributor and the drive gear doesn't appear to have the provision to drive the oil pump.

I am currently working on a putting one of these engines in a 940 volvo station . I am going to be EFI using a older FAST efi ecu. I have been looking at machining the lobes down where the points run and pressing a ford reluctor wheel on and mounting a late 70's ford electronic pickup in the distributor to convert the original merc distributor into a electronic ignition distributor.

 

Their catalog is online so thanks for your suggestion. Variation in thickness can be accounted for by adjusting the timing. I am presently using soft thick paper gaskets.

 

You can do that, but you don't have to as Pertronix makes kits to install their system. Electronic ignition is better when the distributor shaft bearings are worn to looseness or if the contact points are eroded. Barring that, the stock (Kettering) ignition provides a hotter spark for starting so I prefer it. Just do not use an ignition coil for a v8 as with its longer dwell time the coil will draw too much current.

The 3.8 Mercruiser should be a good choice for a Volvo, I suggest changing the cam grind to work better at low rpm. Another nice change is lowering the compression so you can run a vacuum ignition timing advance. When the gasoline changed to lower octane rating Mercruiser's "fix" was to retard the ignition timing causing the engines to run hot.

My stock compression engine ran hot and with a stock cam, was on the edge of detonation but with 8:1 pistons and advanced ignition timing, the engines run much cooler (mine ran 50F cooler F).

Another possibility is to use a swirl pot to remove air circulating with the coolant.

 

I think someone recently posted a water pump conversion for our engine. I thought it was on this thread but I can't find it. Anyone else remember seeing it? I think it would have been in the last couple of weeks.

I made an adapter plate but would like to compare what I have to what someone else did.

 

There was a water pump post on the facebook page recently. I believe they used the Toyota pump.

 

I just looked though my pictures, guess I didn't take a pic. On the facebook page they made a cover to cover the cam hole. I am using that cam hole to mount and run my fuel pump so I welded a wall to the cover near the top to close the water off from the old water pump area. Then made several front cover plates to get my Toyota pump and the fuel pump all on with out running into each other.
I have started work on my second engine and will do the same again.

 

@Flatrod17,
That's it. He was fighting the same issue I'm having. (length)

I came up with a different solution and I believe I gained a bit more than he did.

Will post some pics later as I'm late for an outing with the wife.

 

If engine length is a problem, I'd try an electric pump (about $150).

You could run it off of a $3 relay and a fan switch sensor. Cheap and easy. Fancy electronic controls are nice, but not necessary.

There is a large advantage that a few minutes of high rpm will not take power from running the car. It can be added to the battery later. But if you use a magneto and have no other electrical system, a mechanical drive pump is the only option.

 

Years ago, I found that an early 1970S Toyota Corolla water pump will fit onto a block off plate bolted where the merc water pump was. Run the Corolla pump upside down, it fits easier that way.
You will need a countersunk head machine screw at one point in mounting it so as to not interfere with water flow. A welch plug can be used to plug the camshaft hole but the hole needs to be bored out a little for this. I published a plan for the block-off plate here years ago before page 50. It was a scan of the plate and its dimensions could be used directly as a template for cutting metal.

Someone deleted my plan, they may not have understood what it was.

My only plate is inside a functioning motor so I can't scan another.
Although the toyoto pump gave no trouble, given the advantages of an electric pump, I'd try one of them as they are not expensive and they are very easy.

 

Dennis,
I more or less copied what you did. Changed the orientation slightly to center the fan. I'm trying to be H.A.M.B. friendly and not use an electric fan and/or water pump.

 

Nothing to report on my build. Picked up another core because free. Only reason it wasn't a runner was because some yokel left a plug out and water got in that cylinder.

I think this is an early engine so I'll post pics of the stuff that's different from the other three engines I've dealt with.

Different starter brakect than I'm used to seeing.


Not the usual coupler, but also clearly the "later" flywheels



Different oil pickup. Note how instead of bolting to the main for support it attaches to studs in the side of the block for support.

 

Anyone know how many amps the stock alt puts out? I'm thinking of just using it with an external regulator because my build is slowing and it's one less thing to fabricate.

 

Were the early crankshafts forgings, or were they always cast? I ask because the crank in ARSE_SIDEWARDS pictures above would appear to be cast, in an otherwise early looking block assembly...

 

I don't know early from late, but I have one forged crank and two cast. One more to check in the running motor.

 

The motor I pictured clearly isn't the earliest as indicated by the "late" flywheel.

 

I am going to put some info out that I have been collecting and thinking about, there are some good minds in this forum to pick it apart and open a discussion.

Though this thread I have seen that people are very reluctant to bore out the 470 as the head gasket issues are rightly intimidating. Yet, on the 470’s genesis the 460, Cylinder thickness when bored should never be less than .140 and a lot of original blocks only started with about .165 brand new. Since the 460 is a closed deck you don’t see how thin they really are. Our liners are robust .270 at their thinnest (new). So if you use the minimum thickness rule on our liners you end up with a 4.600 maximum bore. 2.70 – ((4.60 - 4.36)/2 =.12) =.150 thick. This is interesting because this is the maximum bore of the siamesed Ford A460 racing blocks. That said 4.6” even makes me uncomfortable, so let’s say a 4.5 bore is more reasonable. That leaves a .200 thick liner, - not bad and it is still better than an average 460 was new. Of note is the Mahle 470 head gasket is a 4.5” gasket, how convenient – that means sealing would be the same – or at least not be any worse.

Now there are a couple of factors we need to contend with.

1) The Liner. What is the material of the liner? if it is ductile iron there is no problem as it is extremely strong – it may be, but who knows? What our thread needs is someone that worked on the engine at Mercury to answer some of these kinds of questions.

2) The deck - you would absolutely need to reinforce the top of the liners with a deck, as we know that will be the primary failure point.

3) Piston weight, this is overlooked. The stock pistons are heavy, and make up their strength with an abundance of material. I think they contribute to the liner movement and gasket failure, getting the lightest pistons and pins possible would help in any situation. A thinner liner with less mass acting against it may actually be more reliable, not less.

 

not many, but ok for a boat. my fuzzy memory thinks around 25 amps

 

I have a 488 that looks exactly like your free engine minus the water in its oil.
The 488 was made in the early 1980s for a year or two. They also came with a 4bbl carb and 4bbl manifold and a different cam profile. I do not remember about the starter brace as I use a smaller starter that the brace would not fit. but it looks like a well designed brace.

 

Sean My first engine hydrolocked after 2 yrs use (600 miles). Doing that split the cylinder its entire length so I'd not call it strong. It had a 30 thousandth overbore coming to me and I'd only honed it lightly so its new rings would seat.
It was not reinforced at the top.

 

Reducing the compression ratio to about 8:1 helped my engines than anything else they ran much cooler with the timing advance that I could run and still hand good torque. Did not seem to have any less power where I ran it 2200 rpm.

 

This engine is a 2bbl engine.

When I get the starter side by side with my other one I'll take a pic. I think this is the "larger snout" one that someone was going on about somewhere in this thread.

 

Replacement parts are listed as 40 amp

 

I read about your issue on that one. It could be a weak liner, but by the sound of it it started at the top and worked down, lack of a deck to take that peak pressure sure contributed. The crack running, that says it is pretty brittle which shouldn't be the case with any liner. Hydraulic lock is nasty and not much can survive it, stock blocks with a deck will crack a piston or fail too, and fuel cars disintegrate entire blocks in the process.
I will sample a liner and see what it is really made from but my 2 blocks are too good to do that to so I will keep bugging my boat guy until there is one that is that is really unsalvagable to use as a sample. If it is ductile iron then there is an idiot that will bore one out to 4.5" just to see what happens. Me... but it will have a .500 deck plate pressed into it too.

 

PM me your address. I have a core that cracked a cylinder from water intrusion in storage (not the one immediately above) I can cut a chunk out of and mail to you.

 

Just saw that the Speedmaster cylinder heads are on sale for the next few days.

https://www.speedmaster79.com/Ford-429-460-275cc-95cc-As-Cast-Bare-Aluminum-Cylinder-Head

$311.11

I have one and it looks like a quality piece. I'm sure that there are better ones out there, but I didn't need the extra power, I wanted the light weight.