My rapido longblock (pics)

[erikgreen]

Re: My rapido longblock (pics)

I've been trying to get some help from my friends to come over and install, but everyone's busy. Looks like I'll be doing it myself on either saturday or Sunday, solo.

A couple little things have been done.

I have re-installed the transom in my boat, getting it ready to put the engine in. I had to install a new seal O-ring on the outer part (gimble base) and I installed new zincs (acorns) and bolts on the bottom. It took a while to figure out and correct the wire, hose, and cable routing.

I had to work on the bell housing/gimble base outer seal so I could put the new O-ring on... it was pretty corroded, so we wire brushed it and I attached the seal O-ring semi-permanently using a little 3m 4200 on the housing side, so that side is sealed, and I'll rely on pressure from the bolts to seal to the outer transom gelcoat. I did give it a quick once over with 600 grit sandpaper to make sure there weren't any bumps in the gelcoat.

I'm going to try to mount the motor myself as I stated, but I redid the motor mounts in the boat (rot plus broken bolts in them) so I will be mounting the motor, aligning it, drilling holes for the lag bolts, sealing the bolts in place, then running the motor's cam break-in.

I have read in other places on this board the break-in procedure, so I'm planning on starting it, running it up to 2k rpm for an hour, then doing an oil and filter change. I'll also be pre-running the oil pump with a drill before start, and I'll probably use a portable fuel tank for gas to make sure I have good fresh fuel for the break-in.

I also installed new plugs and belts as part of the build finishing, and I'll be putting a new distributor cap and rotor on before the break-in too.

More news soon,
Erik

 

[FreeBeeTony]

Re: My rapido longblock (pics)

Glad to hear you're making progress...........good luck with the install.

 

[gregr1971]

Re: My rapido longblock (pics)

1) Ok. smart guy! the 62' 327/300hp motor was the first engine to have the .390/.410 high lift hydraulic cam, it paved the way for the standard plain vanilla stock Chevy 327/350 cam!

2) I'm sorry No, this just happened a little while after I got the car, the engine was untouched by me at the time, I got it with 40k miles on it.

3) .008-.018 with a feeler gauge with the engine warmed & running.

4) The original Duntov cam was used on the early 55-57 vettes, the Duntov 2 cam was used on the later 283, and the early 62-64' 327- 340, & 360hp corvette engines, look that up in your book! I don't have the rest of the specs memorized as it was a long time ago, maybe (.393-.398 lift, duration?) but suffice it to say the lift, & duration, were not much different then the O.E. hyd. cam, unknowing to me at the time, and I had a chance to get the "30/30" cam then, and thought it was too radical, I wasn't sure if my pistons were notched, (they were)! $32.95 for the Duntov 2 & 16 solid lifters, mechanics discount from the Chevy dealer at the time!

And finally, I think it was 65', that the 097 "30/30" cam came out, called that because it had .030 intake & .030 exhaust lash, it was .480/.480 intake & exhaust lift, and 310 degrees adv. duration. It was the cam I drooled over, with a clicking lumpy idle, and useable power up to 7000rpm. It was used on the 327/365hp corvette with a 4bbl, And the 327/375hp vette with fuel injection. So you see, you're not as knowledgable as you think, ("The "30/30" cam was probably not used on the 327", Ha!) Yeah, the orginal Duntov cam was hotter then the Duntov 2, (a crappy one). Around this time, the 327/350 Hi lift hydraulic came about, it was used in the 327/325hp Chevy 11 Nova, with 10X1 compression, and 327/350hp in the vette with 11.0X1 compression another great cam with .447/.447 lift, and I believe 287degrees duration. A while later when the 350 became the std. engine, the 350/350hp Hi lift hydraulic cam came out with .450/.460 intake, & exhaust lift, and a bit more duration then the earlier 327/350hp cam. and with that, I'm done here on this subject!

those look like plain jane "baby" stock cams!

in that 262, or what ever ci it was, if your rotating assembly was balanced, including flexplate AND dampner, AND the port volumes on your heads were large enough as well as the valves, "i guess they were 2.02 valves", then you would have to have an excellent flowing intake, decent carb, free flowing exaust, MORE THAN AN HEI ignition, dual valve springs( with quite a bit of pressure to control the valve at 5000+rpm), and something better than stamped steel rockers, to make that 7000 rpm mark. JUST BECAUSE YOU CAN MASH THE THROTTLE IN NEUTRAL AND HIT 7000, DOES NOT MEAN IT WILL DO IT WHILE IN GEAR.
I HAVE 2 - SBC 355ci engines that are well capable of pulling 8800 rpm, and these engines i use regularly, one of them is in a street driven car. the other is in my race car, 2- identical builds other than pistons and cams, my STREET driven 93 octane engine will "pull" to 8800 rpm consistently, on pump gas,and a HYDRAULIC cam, 631 hp on the dyno. AND I BUILT THESE ENGINES.
my other engine is a 116 octane race fuel only motor, as it is 13:1 , solid cam, and i use a feeler guage, WARM, engine OFF,to adjust the valve lash.

IF YOU ADJUST A MECHANICAL CAMSHAFTS VALVE LASH WITH THE ENGINE RUNNING YOU WILL BREAK THE CAM!!

If one of you two guy's would like to know how to build a REAL sbc, let me know, i'll teach you!

 

[gregr1971]

Re: My rapido longblock (pics)

i forgot to ad that you must have used those P.O.S. double hump heads to get that 7k rpm. IMPOSSIBLE FOR THOSE HEADS TO SUPPORT 7k!!

 

[erikgreen]

Re: My rapido longblock (pics)

Okay, now that the board is back up again, it's time for an update.

I have a few pictures from this, that I'll try to post later on.

What I did this weekend was finish assembling the engine and put it into my boat. I have not run it yet, but I expect to do so for the first part of the engine break-in on Tuesday sometime.

Here's what I did, in order:

1) Rented a hoist from a local rental shop... it's 10 feet tall and can lift engines in and out of boats. I'm thinking of welding a similar one up from an old boat trailer.. this thing is handy to have.

2) Hoisted the motor into the air. Found out the hoist slowly drops back down under a load. Braced it with a metal tube, it bent. Braced it with an old trailer axle while we worked on it.

3) Installed the bell housing, starter, shift interrupter switch bracket, motor mounts, and attached wiring to the starter on Friday. My helper accidentally snapped off one bolt on the starter to end the evening. Unfortunately, I had dropped my other starter off a workbench earlier in the week, so I was now fresh out of starters. Assembly stopped for the night.

4) Saturday: Went and bought a starter at checker auto - $86 for a refurb model. It's almost completely sealed, so I'll finish sealing it with a little high temp silicone. The model starter I bought needed the inline bolt pattern from the 305 engine, not the one from the 350. Either an inline bolt pattern was used on marine engines that year, or else my block is a bored out 305... this is possible, it's the same block.

5) Installed the starter and with a different helper tried to install into the boat. We got the engine in place, and had trouble with the mounts. First problem was that the starboard mount was bent... from the car accident, again. Fortunately I had spare mounts from a junker boat (helps to have three boats in your driveway) and we got a different mount in better condition.

6) We got the motor in, and bolted to the transom plate. Resting on the motor mounts, we couldn't get it aligned! The alignment tool coming in from the stern was hitting the coupler 1/4" too low to go in. It wasn't a matter of engine angle, but we tried adjusting the mounts, shimming them up, nothing worked. We gave up after a long day of hoisting the motor in and out of the boat. I posted a cry for help here

7) Today: Thinking overnight it had to be something to do with the bell housing motor mounts, I pulled the motor out again and replaced the bell housing with one in a little better shape. I checked the alignment again, no luck.... but, wait! If I push down on the alignment tool a bit the gimble bearing shifts down a little. Success! Apparently the gimble bearing was turned in its housing a bit, preventing alignment. Once it was moved down, then the alignment tool went ok into the coupler.

8) Now that I was close on alignment, I proceeded to get the front mounts drilled and bolted down. I used 3/8" x 5" lag bolts, and coated them liberally with 3m 4200 before installing them. They shouldn't leak, but if they do, the motor mounts probably won't be affected anyway... they're mostly epoxy composite now.

9) I performed the engine/transom alignment. I greased up the tool, and inserted it into the coupler via the transom. The top of the tool didn't get any spline marks in the grease, so I got into the boat and raised the front of the engine a bit (I had removed the earlier shims and lowered the mounts a bit). Once the front of the engine was raised a bit, I re-tried the alignment tool. It went in smoothly, with just enough force to move the tool (it's heavy) and when pulled out I had even spline marks all around.

10) At this point, I forgot to rotate the engine 90 or 180 and check again... I checked the coupler with the tool earlier when it was out of the motor, and it seemed to be ok, so hopefully I haven't missed something by not checking this. I expect the current coupler to last only a year or so anyway, I'll probably replace it early next summer as preventative maintenance.

11) I decided to do a solo install of the sterndrive. My sterndrive was in the accident on the boat, and although I had another one from an older boat, it was still in the best shape of the two. I replaced the broken parts (with one exception) and cleaned the gasket mating surfaces. I installed a new gasket kit onto the transom and outdrive, and then managed to get the thing lifted into place. It went onto the bolts, but then got stuck. I got in the boat to feel where it was, and it was getting into the coupler, but not far. I rotated the engine a little bit, and then gave the drive another push. No luck, so I gave it a "Mercruiser kick" which settled it into place and let me put the lock nuts on. The nuts pulled the drive snug, and I torqued them into place.

12) I pushed the trim cylinders until they were even, then attached them to the drive. It's partially trimmed up at the moment. I expect to replace the drive, too, within a year, probably with an SEI unit. This drive has cracks in the housing around the cross bolt for the trim cylinders.. I don't think it's anything but bent metal there, and there's no leaks, but long term it can't be good. I'll try to post a pic tomorrow of this.

13) I spent some time working in the boat, attaching lines to the trim pump, the trim sender, the upper and lower shift cables, the throttle cable, the power steering, and the shift interrupter. I still have two wires with eyelets, black and grey, coming out near the interrupter switch. I have to look them up, I think they go to there. Likewise, I still have to connect the main battery cables and plug in the mercruiser connector.

14) I plugged the old sight glass outlet on the fuel pump with a brass plug. I won't have an indication of diaphragm failure for now, but I can live with that.


I still need to use a pipe tap on the temperature sender socket, then mount the sender in place with a bit of thread lock. This shouldn't be a big deal, but we'll see how it goes.

Tomorrow or Tuesday, I will put oil and ATF fluid in the engine and power steering respectively. I'm pretty sure I'll need 5 quarts, but I'll look it up.

Once I get the battery connected, I will use a tool I made from a screwdriver in my drill to run the oil pump and circulate oil through the engine.

Then I'll install the distributor, and put the cap on. I have a portable boat fuel tank I'm filling with fresh gas. I want to use a boat tank that hasn't been sitting for a couple months in case there's any problems with the fuel in the other one - this will eliminate fuel as a cause of any issues I have with the new motor during the break-in run.

Then it's time for the cam break-in. I expect to run the motor at about 2000 rpm for an hour, then change the oil and filter. After that, it's off to the lake for a shakedown!


Erik

 

[Gary H NC]

Re: My rapido longblock (pics)

Sounds like you got a bunch done! Good luck on the first start up Erik!!

 

[erikgreen]

Re: My rapido longblock (pics)

Well, no luck on the first start.

I got the last bits of the block done, the temp sender in, put in oil and ATF fluid, circulated the oil with a screwdriver blade in a drill, filled the trim pump, tested it, and tried to start.

No dice... not even a click from the solenoid. Might be my battery, but more likely there's a bad connection somewhere. I did have power at the console, but there still might not be enough to crank the motor.

Or, it might have been the torrential rain coming down that messed something up.. I was working under a tarp and soaking wet the whole time

Tomorrow, if I get a chance, I'll trace the wiring and look for questionable connections.

Erik

PS: One bad thing, my fuel pump connections were loose and leaked a bit. I'm going to pull them apart and re-tighten with teflon tape... not sure that's the right thing to use, but they need to not leak gas.

 

[Dante04SRT]

Re: My rapido longblock (pics)

PS: One bad thing, my fuel pump connections were loose and leaked a bit. I'm going to pull them apart and re-tighten with teflon tape... not sure that's the right thing to use, but they need to not leak gas.

There is a special thread sealer made to be used around gas. From what I've read, teflon is not advised for gas applications.

 

[erikgreen]

Re: My rapido longblock (pics)

It started!

We spent a little time today getting the timing right. I bought a timing light and a battery charger, charged up the battery fully.

After tweaking the timing a bit, the motor started. It ran really rough, and we adjusted the distributor by ear, which made it hum along.

It sounds like there's more rubbing and grinding than usual for a motor going on, but nothing extreme. I'm guessing newly rebuilt motors sound a bit rough at first?

The exhaust looked ok, although it was a bit more steamy looking than I'd like, it wasn't billowing clouds of steam.

I had the outdrive in a livestock feed tub of water, so I could test the lower unit impeller. The motor took up at least some water, and the exhaust and water came out the relief holes, so I know it's at least circulating ok.

The temperature gauge stayed in the green the whole time, and my portable IR thermometer said the risers were at about 110-135 degrees F. The rest of the engine seemed cooler.

We ran the motor for about 5 minutes at a time, just enough to get the timing right. Next time I start it I'll probably be on a lake, and ready to begin the break-in cruise (I discovered break-in should really happen under load, so I'm going to do it on a lake).

So far things look pretty good, although I was nervous about doing something wrong and destroying the engine the whole time.

Erik

 

[erikgreen]

Re: My rapido longblock (pics)

Okay, I completed the 20 minute cam break-in.

As discussed in another thread, I may or may not have messed things up by running the engine for 5 minute intervals while I was getting timing working. I guess we'll see what happens going forward.

The break-in also let me check temps. Maximum temps encountered were as follows, as measured by my IR thermometer:

Top of thermostat housing: 142F
Top of starboard log manifold: 183F hot spot, mostly 150-160F
Top of Port log manifold: 150-160F
Intake manifold under carb: 250F
Front of block: 110F
Lower thermostat housing: 110F

All through the run, I had warm to hot water coming out the relief holes in the transom. I also had exhaust, although not a lot of steam.

All in all I'd consider this a successful run, although there are still a few things I want to watch and still a few noises I don't recognize.

The pulley on the harmonic balancer may be a bit bent, it almost looks like it's wobbling a bit (may be an illusion). I had a loose belt when I started, which screeched a lot at 1800RPM until I stopped and tightened it. There's still more noise than I'd like coming from the block, but maybe that's just due to the lack of break-in.

With luck I'll get it to the lake this weekend, and we'll see what happens.

Erik

 

[mbroome]

Re: My rapido longblock (pics)

I ordered my rapido 305 block last monday, stinks not having my boat this weekend. I wish I had read this earlier. Im gonna email Raul and see if I can get my 10% discount back! BOO!
another thread related to this:
http://flagislandms.freeforums.org/here-we-go-again-sigh-my-blown-motor-t48.html

I'll post my pics and overrall impressions as well!

 

[mbroome]

Re: My rapido longblock (pics)

in and running! If anyone is interested,
http://flagislandms.freeforums.org/here-we-go-again-sigh-my-blown-motor-t48.html

Rapido earns my recommendation!

 

[Limited-Time]

Re: My rapido longblock (pics)

So what H.P. are you hoping to get from this engine?

Why are you last 2 posters tagging onto a 8 month plus old post??

 

[mbroome]

Re: My rapido longblock (pics)

who cares how old the thread is, its directly related and will help others! Horsepower wise I'm not really sure. The old block was a 200 horse (supposedly). I have no clue what I will get out of the new motor. I am doing the break in saturday......

 

[rock_doctor]

Re: My rapido longblock (pics)

Augh! I hate it when an old thread is reactivated....but it would be nice to hear how everything worked out. Any updates from Erik???