Hi Joe, This is Tom from D Dock at the Shore Club with the 69/35SC. A late 80s early 90s CBB would at the latest be a Mk V motor which would still have flat tappets. I have not seen a recent oil analysis on Quicksilver 25/40 and they don't publish their ZPPD levels. I would guess, since it is formulated for modern boat engines with catalytic converters, it is probably in the 800-900 ppm range. If you have been running it in your motors, I would probably send a sample to Blackstone labs for an analysis - then you would know for sure and the analysis would tell you if you have any other issues. It is a relatively inexpensive piece of mind.

You can make one yourself, but I just bought the standard Crusader gasket from the local marine store. The intake manifold should be the same on all the marine conversions. Mine are raw water cooled and from the early 80s.

The part number for the Barr riser gasket is 1-0107 for raw water cooled (open water passages) and 1-0105 for the closed cooled (blocked off water passages).

A standard thermostat housing gasket is used on the 454. Can use a Crusader or Merc one from any Marine store.

It looks like the exhaust manifolds were replace with the Barr type. They used the same gaskets on their three and four inch risers. Michigan Motorz should have them.

I will try to pull a bolt & spacer to measure this weekend. Lee is correct that it is a good idea to use a support bracket on those pumps. The commercially available brackets force you to locate the tapped hole at 6 o'clock which may not be the best routing for the hoses (mine sits at about 4-5 o'clock). I may make a bracket from bar stock or angle iron to tie into the old CC mounting bracket.

The Sherwood pump had the discharge hose going to the tee via a regular street elbow that was soldered into the tee. I had to heat that up to remove, and then solder a piece of straight tubing to get past the alternator belt. I purchased a hose with a molded 90 degree elbow to connect with the pump discharge. I used a new wire reinforced hardwall supply hose from the pickup to the pump. Much easier to service the impeller and a much shorter run to the pickup. You will need to get longer bolts for the pulley and spacers for the larger diameter holes in the pump flange to make sure it is perfectly concentric (or swap out the pulley for one that has the corresponding detents to the pump flange).

Any restriction at the cooler is bad. There is a Tee where water is split between the coolers and the thermostat housing (check the thermostat housing for debris too). A blockage at the engine cooler will divert more water to the thermostat housing and reduce the water going through the engine oil cooler, the transmission cooler, the pressure relief valves, then back up to the exhaust manifolds. The balance of the 140 degree water going through the engine then the front of the manifolds will be different between the ambient temperature of the water entering the back of the manifolds via the pressure relief valves. It is a good idea to use an infrared temp gun to check the temp of the transmission coolers when running every once in a while. I usually back flush my coolers once a year too. I made a hose fitting with a garden hose adapter - just pull the hose from the bottom of the pressure relief valve housing and insert the hose fitting. Then pull the hose (1 & 1/4 I believe) off the front of the engine oiler. Run an extra piece of hose from the cooler into a 5 gallon bucket & turn on the garden hose. Easy to do & only takes a few minutes.

Good idea to check every season after it has been in the water for a while. My hull (1969 35ft SC) doesn't move a bit over the winter, but I still check it. Keep in mind that when under way, it is always moving in and out of alignment as rubber motor mounts and hull flexes. This is where a flexible coupling like the Federal Flexible Coupling may reduce some wear on the back end of the transmission (also when shifting in forward & reverse while maneuvering in the harbor). As the rubber bushings in the motor mounts settle, alignment will change a little. Good idea too to spray your coupling faces with WD40 to make it easier to separate them to check with feeler gauge. If you really want to go nuts, you can set up a dial indicator and check the shaft runout while underway.

Hopefully they put hardened seats in for the exhaust valves when they did the rebuild. Marine fuel was still allowed to use lead well after it was banned for automotive use and the marine industry lagged behind in using hardened valve seats (probably lots of NOS heads awaiting assembly). I have mid 80s BBCs and use Lucas Upper Cylinder lube just in case, plus it may help to prevent valves from sticking over lay up.

If you turn the block around to run off the "correct" end, your rotation may be the wrong way for the trans. Would need new oil pan, front cover, bell housing, exhaust manifolds, water pump etc.. Relatively inexpensive for the SB Chevy but a lot of work. May want to look for a good used marine SB - Merc or Crusader.

Hey Mike, Make sure you stop by next time you are in SE Michigan!

My tanks are original. They look good from the outside and never had an issue with filters loading up - so I am knocking on wood!

Yes, I installed a Johnson F6B-9 crank mounted pump. It really shortened the length of hose to the raw water pickup and seems to pump more water through the engine at idle. It is also much easier to service the impeller. CC soldered a regular street elbow into a Tee where the the water from the pump went to the engine oil cooler and split to the thermostat housing. I took the elbow out and soldered a straight piece of copper tubing into the Tee and used a hose with a molded elbow to clear the alternator belt. You will also need longer bolts for your crank pulley and spacers (bolts are smaller diameter than mounting holes on pump flange) to mount the pump. My engines are raw water cooled, so may be a different setup if yours are fresh water cooled.

I replaced mine two years ago with the Barr CHVA-1-84s. They make 3 or 4 inch risers to go with them and my CC dumps were 3.5 inches - so had to make a small step down at the crossover pipe. The Barr's were slightly lower than the Mercruiser types so they gave a little more deck clearance plus they could be plumbed from the front and back allowing use of the existing hoses. You will have to relocate your oil filter bracket and fuel filter bracket if they are attached to the manifolds.

Those are pretty good numbers for that boat. Probably a good way to go, the Crusaders were rated at 270 hp which is significantly better than the CC SBCs which were rated from 210 - 235hp.

Like Mike said, it is a tight fit with the center rise exhaust manifolds on the 454s because of the shaft angle (15 degrees) that CC used and the off set drop of the Paragon transmissions. If you have Velvet Drives on your 454s, that will drop the height 1.5 - 2 inches. You may get better fuel economy with the 454s because they won't be working as hard. I cruise at 16 - 17 mph and only turn 2600 rpm with the 2.5:1 reduction gears. The P34s were rated for 260 hp, but my cruise speed is under that according to the published hp curve.

I'm pretty sure it was Stewart Warner that made them for CC in those years.

If it is a 327 F (starter & flywheel in back of engine), maybe easier to access by removing riser. I have had good luck with Arco (so far).