Monsoon II Oil Pan Replacement Project

[Bozboat]

1999 SSLXI, Monsoon II 

 

This April, I am going to pull the engine out and replace the original oil pan.  Several reasons for this.  1) the original oil pan has some rust on the bottom near the drain, 2) I bought a really cool 7 quart Indmar Custom Moroso OIl Pan from EngineNut two years ago,  3) the drive flex plate rattles some at idle, and 4) at close to 700 hours, I would like to replace the strut bushings.

The plan is to pull the engine, pull the oil pan, replace the oil pump, replace the oil plan, replace the flex plate,  replace the strut bushings, put the engine back in and align the driveshaft.

Any suggestions on which oil pump  and pick up to purchase?  (Seems like a good time to put in a new oil pump.)

Should I paint the oil pan?

 

[MadMan]

If you plan on keeping the drain hose, be aware the GM went metric at some point on drain plugs.  Your current hose adapter might not have the same threads as the Moroso pan.

[Woodski]

If you plan on swapping to a new oil pump, I would get a GM hi flow pump but in reality you don't need any more than what the current pump delivers.  The marine engine spins pretty slow and an oil pump volume is related to engine speed so that should provide plenty of oil at lower speeds.  The bearing clearances are not anything extreme so your options are pretty wide open on choices.  Personally, if I were adding a high volume pump I would probably add a crank scraper to ensure the draining oil does not get whipped as crank windage.

You will want to paint the pan for corrosion resistance.  I would make my own drain hose, easy to gets parts at a local hardware store.

Note:  with that pan you won't drain all the oil out at each oil change due to tilt (unless you do it on a ramp nose downhill).  Not really a big deal as it will be a small amount.

[Michigan boarder]

When we did my engine overhaul we put in a Melling high volume oil pump.  At idle it reads 40psi and it reads 60psi at speed.  I really like seeing the pressure remain high even on a hot day after a footing run, rather than it dropping well below 20 with the old pump.

[oldjeep]

26 minutes ago, Michigan boarder said:

When we did my engine overhaul we put in a Melling high volume oil pump.  At idle it reads 40psi and it reads 60psi at speed.  I really like seeing the pressure remain high even on a hot day after a footing run, rather than it dropping well below 20 with the old pump.

Any pump should be putting out 40 at idle and 60 at speed unless the pump or your bearings are shot.

[Bozboat]

8 hours ago, MadMan said:

If you plan on keeping the drain hose, be aware the GM went metric at some point on drain plugs.  Your current hose adapter might not have the same threads as the Moroso pan.

I ordered a hose and adapter from Bakes, will see what if it fits.

edit: banjo fitting fits the pan but  I don’t know why they call it “banjo”

Edited March 15, 2018 by Bozboat

[Bozboat]

1 hour ago, Woodski said:

If you plan on swapping to a new oil pump, I would get a GM hi flow pump but in reality you don't need any more than what the current pump delivers.  The marine engine spins pretty slow and an oil pump volume is related to engine speed so that should provide plenty of oil at lower speeds.  The bearing clearances are not anything extreme so your options are pretty wide open on choices.  Personally, if I were adding a high volume pump I would probably add a crank scraper to ensure the draining oil does not get whipped as crank windage.

You will want to paint the pan for corrosion resistance.  I would make my own drain hose, easy to gets parts at a local hardware store.

Note:  with that pan you won't drain all the oil out at each oil change due to tilt (unless you do it on a ramp nose downhill).  Not really a big deal as it will be a small amount.

I ordered the "banjo" fittings and a hose.  Its 60 inches, so I need to either cut it down or make my own like you suggest.    Do you see any reason to swap the oil pump while I have the pan off?   I am betting its a 50/50 chance that I will save any of my labor if the old pump fails vs the new pump failing.   I have only had one oil pump fail in my history of owning vehicles.

[oldjeep]

4 minutes ago, Bozboat said:

I ordered the "banjo" fittings and a hose.  Its 60 inches, so I need to either cut it down or make my own like you suggest.    Do you see any reason to swap the oil pump while I have the pan off?   I am betting its a 50/50 chance that I will save any of my labor if the old pump fails vs the new pump failing.   I have only had one oil pump fail in my history of owning vehicles.

60" sounds great, out the bilge and right into the pail.

[MadMan]

28 minutes ago, Bozboat said:

Do you see any reason to swap the oil pump while I have the pan off? 

While the oil pump is literally (I hate using that over used word) the best lubricated component in the engine, it is lubricated with pre-filtered oil.  Consequently, it ingests everything that can make it through the pickup screen.  When you get the pan off, you can disassemble the pump to inspect the rotors.  Or, since a small block Chevy pump is the cheapest pump you can buy,  don't bother and just get a new one.

[Woodski]

@Bozboat: On pump replacement probably no need, but @MadMan makes excellent points.  Although if you look at failure data, mid life is the most reliable, there is a reason for it being called infant mortality and it strikes hard parts too.  A failure point on the pump is also the distributor, basically the device that drives it.

[Bozboat]

Painted today

[Bozboat]

Anyone know how much a Monsoon ll with iron exhaust manifolds weighs?  

(Skidim  list 950 pounds for a a complete PCM 5.7 liter drop in)

thought I might need to know that before I trying to pull it with an overhead hoist

[Woodski]

@Bozboat:  Not sure on the Monsoon, a Mercruiser is 888 # and one with serpentine drive is 946 #, so your 950 # is probably reasonable, a velvet drive is 95 #.  Those exhaust manifolds are 65 +/- lbs each, so if concerned pop them off.  A long block is 450 # so that kind of gives you the long block to fully dressed comparison.

[Bozboat]

[Bozboat]

[MadMan]

14 minutes ago, Bozboat said:

Yours is just like mine was, 2-bolt mains, cast crankshaft, nothing special, contrary to popular belief.

[Bozboat]

Well, the custom Indmar by moroso oil pan fits the engine but not the boat. Turns out the raw water intake is in the way, by about two inches.  If the intake had been installed two inches back or one inch out all would have been well.  Random raw water intake placement struck me down.

Will pick up a stock oil pan tomorrow and try again.

Also can’t figure out how to get the transmission off the engine. Took off the two bolts and the two nuts (four points) but it won’t budge. So the damper plate upgrade may get postponed.

I did get the strut bushings replace wit the  newer plastic ones.

Edited May 20, 2018 by Bozboat

[MadMan]

8 hours ago, Bozboat said:

Took off the two bolts and the two nuts (four points) but it won’t budge.

There are 6 total.

[justgary]

Boz -

Too bad about that pan.  Modding it to fit should be straightforward if you want to continue the adventure.  

Thanks for the good photos.

- Just Gary

[Woodski]

@Bozboat:  If you want to continue your oil pan install, one option would be the Indmar crank mounted version. Another option would be to install a Jabsco style (Sierra also makes a copy) sidewinder or belt driven raw water pump if a crank drive version is the issue.  Mercruiser uses this type of pump, so you could get Merc brackets and since a belt drive setup, you can actually position it more where you need it with some bracket modifications and a belt the length you need. You could also slice and dice the Moroso pan to fit which may be a less costly option.

Nice pic and can be used to really show effect of oil level on the potential of crank windage if one is to overfill the oil level.  You can see the dipstick in the picture, and if you were to tip the engine or simply take a long straight edge and set it to the installation angle in you boat where the oil level on the dipstick is, you can observe if the oil level would rise above the windage tray and potentially get whipped by the crank.  You can also see the relationship of the oil intake bell and the dipstick level.  Most folks reading this post are probably up to speed on it, just thought I would add.

Edited May 20, 2018 by Woodski

[Bozboat]

I picked up a stock oil pan at the auto parts store.  New OEM for SBC comes with a windage tray.  Boat has a tray attached to bottom of engine. So we cut the tray out of the new pan. Here is a picture before we cut it.

[Bozboat]

Onto the Next problem. The original oil pan has a standard thread drain plug, oil pan number three has a metric drain plug.  So I had to stop and will order the metric hose adapter drain plug before installing the engine.  Here is where it sits until I can get back to it.  The moroso sticker on the stock oil pan made me feel a little better. Lol.

[Bozboat]

@woodski

The Indmar 7 quart moroso oil pan is that it is 2-4 inches wider at the bottom.  The brass raw water intake thru Hull is two inches to far forward or an inch too close to the center of the hull, so the pan won’t fit in the boat without modification of the pan or relocation of the thru Hull. Neither option appeals to me from a time issue this late in the the Spring.

re: oil levels:   the engine in a direct drive orientationin a boat like mine at 20 mph would be quite an angle. 

[justgary]

Boz -

It's a good time to change the exhaust hoses and fuel lines if you haven't done that recently.  

Did you get the transmission off?

- Just Gary

 

[Woodski]

@Bozboat:  The thru hull modification is only a hole in the bottom of your hull, what could possibly go wrong... Once you drill one hole, the next ones do get easier.  Metrification strikes again, your boat suffers from  glorious era of sorta, trying to go metric...