Author Topic: CVZ-18 hull rebuild has begun!  (Read 53674 times)

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Offline Plugcheck

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Re: CVZ-18 hull rebuild has begun!
« Reply #80 on: January 06, 2017, 02:53:36 PM »
       That is the cam that I'm running and have been pleased with it.   Lots of snake oil salesmen in the camshaft world, but I think you will be pleased with that one.  Port matching helps at all rpm ranges.  Larger valves and better flowing heads will help, but weigh the costs is my point.  One item to consider is the distributor since we have discussed yours being a 350, but was it a car engine before?  The reason that I ask, is that the Dist. needs to be an all centrifugal advance unit, no vac advance unless your carb can supply the vac signal.  I rebuilt the 898 merc dizzy on mine and tuned the curve to be all in at 2200 rpm running a total of 28 degrees for break in.  Moved up to 30 degrees this year, so I may go up to 32-34 with some testing this year.  I don't get out as much as I'd like to.   BTW, found some heads on craigslist for $100-125 a pair, indicating Christmas bills must be starting to hit.
Michael
1979 CVZ-18 388 CI Vortec Mouse
1980 CVX-16SS 140 Mercruiser
1979 CVX-16 Johnson 175
2002 Bennington 2275CC 90 Mercury
1985 Intimidator project
1989 Lowe 200 Redneck fishin Toon
2001 Godfrey Sweetwater pontoon 115 Rude

Offline Scott in nh

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Re: CVZ-18 hull rebuild has begun!
« Reply #81 on: January 06, 2017, 03:05:14 PM »
Thanks for the info!

All indications are that it was a mercruiser 260 engine fitted with all the accessories from the original 898/305 including the mechanical advance distributor (i.e. no indications the engine was ever anything but black).

Judging by the cracked but fixed with epoxy exhaust log, I would say that they likely did not winterize the motor and froze the 305.

Depending on what I find this weekend, I might be searching for heads on Craigslist too! Or as you suggested, I will disassemble and clean myself and just have the shop do the seat and valve grinding.

I think some more advance will wake your motor up, but understand why you are making several small advance changes!

Offline Scott in nh

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Re: CVZ-18 hull rebuild has begun!
« Reply #82 on: January 17, 2017, 01:18:03 PM »
Ok, so short history before I bring you up to speed and ask for advice.
I bought the boat 2 years ago and it had sat unused for or lightly used for 2 or more years.
It came with what was supposed to be a mercruiser 260 from another boat with unknown hours or history, but ran on muffs.
I have verified from the block number that it is in fact a 350 engine, but virtually all external parts, intake, carb, distributor, exhaust, even the valve covers came off of the 305.

After the first year outside, I took the engine out and put it in a heated basement without ever trying to start it again.
I did a compression check but did put a small amount of oil in each cylinder because it had been sitting so long.

I cranked the engine over quite a bit, but never added more oil and I got 140-150 on all cylinders except one that  was 130 - 135.
Jump forward one year, I have a small compressor and decided to redo the compression check and at least attach the compressor to listen to where the air is going.

I had put some marvel mystery oil in each hole a year ago, but did not add more oil to the cylinders for the retest.
This time I go this:
#1 150
#2 60
#3 120
#4 130
#5 150
#6 150
#7 100
#8 150

I did not get around to doing a leakdown on all of the cylinders, but did test #1 and #2 and i could here air in the intake in both cases and it really didn't sound much different. I think I need to finish doing the leakdown test (or do I?), but am I likely looking at cracked rings in #2 or might the rings have stuck themselves in the groove?

Assuming the pressure goes up when i add oil what do I do?

Remanufactured long block? Plenty of options out there - how do I find a good one at a good price (I found one as low as $1500)?

Buy a rotating assembly kit, have the heads done and the block bored? If so is it worth going to a 383? Similar costs to a reman (maybe even a bit more, but at least I know what I have).

Do the heads, hone and re-ring and call it good? Cheapest option, but.....

Buy a "good" long or short block on Craigslist? Ok, this is probably even cheaper.




Offline Plugcheck

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Re: CVZ-18 hull rebuild has begun!
« Reply #83 on: January 17, 2017, 01:43:33 PM »
     Since the compression checks have resulted in low readings versus the readings you had previously tells me the rings have likely taken a set.  Your options are varied, but honestly, without putting it in the boat and wringing the cobwebs out of it, its hard to tell if it really needs work or not.  Rings set, lifters bleed down, seals dry out, etc.....   Running it on a stand really imposes no load, so getting the rings to move might be a problem.   If it were me, I'd either run it as is, tune it up and see all the while saving my pennies for bad news, or do a complete tear down and inspection since its winter and not much else is going on boating wise.   
Michael
1979 CVZ-18 388 CI Vortec Mouse
1980 CVX-16SS 140 Mercruiser
1979 CVX-16 Johnson 175
2002 Bennington 2275CC 90 Mercury
1985 Intimidator project
1989 Lowe 200 Redneck fishin Toon
2001 Godfrey Sweetwater pontoon 115 Rude

Offline Scott in nh

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Re: CVZ-18 hull rebuild has begun!
« Reply #84 on: January 17, 2017, 03:02:09 PM »
Thanks Michael,
Should I use more MMO to try and release the rings or maybe pour some Seafoam instead?

Offline Plugcheck

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Re: CVZ-18 hull rebuild has begun!
« Reply #85 on: January 17, 2017, 03:54:27 PM »
    The MMO will function as a better cylinder lubricant and preservative for storage.  Neither product, IMHO, would work to break rings loose just by sitting.   Combustion pressure on the backside of the ring does that.  Run it, let it cool down, then check compression.  Its somewhat difficult for me to tell you an exact course of action, because there is not just one way to do it.  All depends on your goals and budget.  You want ultimate power and reliability and have $15K laying around, well that's one path.  You want decent power, reliability, and have a budget of $1000.00, well that's possible too.  I'm just not certain your engine is bad or in need of full rebuild because a few compression points are low.  The CVZ/CVX design allows for fairly quick engine swaps, I'd probably save my money, and run what ya got at least to test things.   Now if you come across a great deal, well maybe that is the way to go, but then your never certain just how good that engine is.   A tear down and inspection would tell you everything you need to know, but you need the tools and experience or someone who can do that for you.  Getting to know a local machinist or good mechanic is a good thing.  Beer money spent wisely can yield great things(should be a sign in my shop)
Michael
1979 CVZ-18 388 CI Vortec Mouse
1980 CVX-16SS 140 Mercruiser
1979 CVX-16 Johnson 175
2002 Bennington 2275CC 90 Mercury
1985 Intimidator project
1989 Lowe 200 Redneck fishin Toon
2001 Godfrey Sweetwater pontoon 115 Rude

Offline Glastronjohn18

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Re: CVZ-18 hull rebuild has begun!
« Reply #86 on: January 17, 2017, 04:42:09 PM »
Quote
Getting to know a local machinist or good mechanic is a good thing.  Beer money spent wisely can yield great things(should be a sign in my shop)

What great advice Mike. That's probably why my boat projects are at a stand still......not spending enough beer money.
John
'80 CVX 18 - Survivor Class
'78 CVX 18
'76 V 225 -   Bal Harbor
'80 V195XL
'86 CVX 18- And '86 Makes 3

Offline Scott in nh

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Re: CVZ-18 hull rebuild has begun!
« Reply #87 on: January 23, 2017, 12:43:06 PM »
    The MMO will function as a better cylinder lubricant and preservative for storage.  Neither product, IMHO, would work to break rings loose just by sitting.   Combustion pressure on the backside of the ring does that.  Run it, let it cool down, then check compression.  Its somewhat difficult for me to tell you an exact course of action, because there is not just one way to do it.  All depends on your goals and budget.  You want ultimate power and reliability and have $15K laying around, well that's one path.  You want decent power, reliability, and have a budget of $1000.00, well that's possible too.  I'm just not certain your engine is bad or in need of full rebuild because a few compression points are low.  The CVZ/CVX design allows for fairly quick engine swaps, I'd probably save my money, and run what ya got at least to test things.   Now if you come across a great deal, well maybe that is the way to go, but then your never certain just how good that engine is.   A tear down and inspection would tell you everything you need to know, but you need the tools and experience or someone who can do that for you.  Getting to know a local machinist or good mechanic is a good thing.  Beer money spent wisely can yield great things(should be a sign in my shop)

I am going to buy a boroscope that works with my iPhone and take a look inside the motor.
If I see something distressing I will repair/replace the heads or get a long block as appropriate.

If not, I'll mount the engine on an engine stand so I can level the cylinder bank and start a treatment of MMO.
It is still several months away from going back in the boat.

Thanks for your feedback!

Scott

Offline Scott in nh

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Re: CVZ-18 hull rebuild has begun!
« Reply #88 on: August 09, 2017, 10:52:29 AM »
So work travel, weather, life and other projects have gotten in the way, but I am starting to get back on it!

Time to cut the keyhole and am looking for advice on the best jigsaw blade and technique.

While cutting wood in general with my jigsaw, the cuts are not always the same on the bottom of the cut as on the top I would assume due to blade deflection - am I just cutting to fast or is there some other technique I am missing?

What about drilling the bolt mounting holes true and square?

Most of my other screw ups can be fixed or covered, but not this one - so I need to get it right the first time!

Thanks and "Hi"!

Scott

Offline Plugcheck

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Re: CVZ-18 hull rebuild has begun!
« Reply #89 on: August 09, 2017, 02:04:39 PM »
      A jig is available for the keyhole, but it is a bit pricey.   when I did mine, I marked it with a paper template, then drilled out all the turns in the pattern.  I went about 1/2 deep with a 3/16 bit with a hand drill, then used a 3/8" bellhanger bit(24" long) with a 2" thick aluminum guide block to insure the bit cut square to the transom.   There is a tool to do this, I just don't own one.  A good small square can work as well.   Take your time.   Then used a jig saw with long course blade and went slowly.  You have to finish a bit with a carbide burr to shape the area where the steering arm travels at the top, or your turning angle will be limited slightly.  I just used the grinder to radius the rest of the shape.   You must reseal the now open wood pores to prevent rot.   
Michael
1979 CVZ-18 388 CI Vortec Mouse
1980 CVX-16SS 140 Mercruiser
1979 CVX-16 Johnson 175
2002 Bennington 2275CC 90 Mercury
1985 Intimidator project
1989 Lowe 200 Redneck fishin Toon
2001 Godfrey Sweetwater pontoon 115 Rude

Offline Scott in nh

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Re: CVZ-18 hull rebuild has begun!
« Reply #90 on: August 09, 2017, 03:44:11 PM »
Thanks Michael,

I have the original opening in the hull as a template for cutting, my concern was the inside of the transom not matching - I will drill out the corners using a guide block to keep it true rather than trying to cut them with the saw (good point)

I was already thinking about making a guide block for drilling at work using a drill press and will use it for drilling the mounting holes too - thanks for the confirmation.

I recall the upper corners were angled outward (on the inside) for clearance and will drill or grind accordingly - tight turns are required for docking and skier recovery!

The bad news is it is not looking like I will get her wet this season

The good news is that it gives me enough time and money to consider re-powering with a crate motor rather than do all this work only to be disappointed in the way she runs

Scott


Offline Plugcheck

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Re: CVZ-18 hull rebuild has begun!
« Reply #91 on: August 09, 2017, 04:08:21 PM »
     Nothing wrong with crate engines per se, just make sure it comes with some form of warranty.  Shawn(fireman24mn) purchased a complete stroker engine to go in his refurbished 23, keep an eye on his thread.
Michael
1979 CVZ-18 388 CI Vortec Mouse
1980 CVX-16SS 140 Mercruiser
1979 CVX-16 Johnson 175
2002 Bennington 2275CC 90 Mercury
1985 Intimidator project
1989 Lowe 200 Redneck fishin Toon
2001 Godfrey Sweetwater pontoon 115 Rude

Offline Scott in nh

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Re: CVZ-18 hull rebuild has begun!
« Reply #92 on: August 09, 2017, 05:57:39 PM »
     Nothing wrong with crate engines per se, just make sure it comes with some form of warranty.  Shawn(fireman24mn) purchased a complete stroker engine to go in his refurbished 23, keep an eye on his thread.

I do have some anxiety over finding a rebuilder that offers a consistent, reliable product.

It makes me consider rebuilding what I have.

What do you think of getting a brand new Chevrolet motor and swapping in a marine cam and brass freeze plugs?
« Last Edit: August 10, 2017, 08:34:07 AM by Scott in nh »

Offline Plugcheck

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Re: CVZ-18 hull rebuild has begun!
« Reply #93 on: August 09, 2017, 11:58:22 PM »
I doubt most street engines, factory specs, will come with too radical of cam.  Just ask, they will tell ya.  Duration is key, try to stay under roughly 285.  A 280 is a fine rv type torque cam.  You could run steel frost plugs, but they will rust in time since there is no additives in the coolant.  Easiest to change when on a stand.  Jegs and Summit offer good engines for the price.  Costly things are the marine dizzy, fuel pump, carb, starter, etc..   
Michael
1979 CVZ-18 388 CI Vortec Mouse
1980 CVX-16SS 140 Mercruiser
1979 CVX-16 Johnson 175
2002 Bennington 2275CC 90 Mercury
1985 Intimidator project
1989 Lowe 200 Redneck fishin Toon
2001 Godfrey Sweetwater pontoon 115 Rude

Offline Scott in nh

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Re: CVZ-18 hull rebuild has begun!
« Reply #94 on: August 10, 2017, 08:32:30 AM »
I've been looking at Jegs and Summit all along, they both have good products and excellent service!

The new Chevrolet Performance engine is attractive because it is brand new, not rebuilt, for about the same money, but they clearly call out "not for marine use".

http://www.jegs.com/i/Chevrolet-Performance/809/12681429/10002/-1

My assumption is because of the cam and freeze plugs, as it is only a long block.

Luckily I have all of those costly marine parts except for the 4bbl carb (the manifold and carb from the original 305 were put on the 350 it came with, but I already bought a 4bbl manifold).

Offline dorelse

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Re: CVZ-18 hull rebuild has begun!
« Reply #95 on: August 10, 2017, 09:30:08 AM »
I'm not sure if this is helpful...but...when I rebuilt my CVZ, I asked around and found a highly recommended engine shop in town with experience rebuilding marine engines.  I was quoted $1700 for a mine (granted it was a 305) and I brought them nothing.  They had a mercruiser block, heads and parts already done and prepped and essentially put it together for me, intake, distributor, plugs & wires, everything.  For an extra $150, they rebuilt my carb, timed it and I walked out of there 2 weeks later with an engine I could drop into Goldie.

(Through a lucky break, they knocked $500 off the price, so my out the door price was $1350.) 

If you find the right local shop, you might come out ahead.
1990 Sierra 1700

Offline Scott in nh

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Re: CVZ-18 hull rebuild has begun!
« Reply #96 on: August 10, 2017, 09:48:47 AM »
Thanks for the reply, it is helpful and discussion worthy,

I do have a highly regarded local shop that has done work on my streetbike and my brothers 8 second dragbike.

I have and am considering it, and it is fun when you are not in a rush to build an engine, but it does not save any money over just having one dropped in my driveway ready to go.

I am also concerned that I would spend a couple hundred dollars only to find out the block or heads are unusable.

This is what happened with the motorcycle jugs I dropped off to be honed (it cost me $100 to have the gaskets machined off before he could jig them and put torque plates to measure the bore which ended up not being round - trust me there was no other way to get the base gaskets off without damaging the jugs)

Offline Scott in nh

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Re: CVZ-18 hull rebuild has begun!
« Reply #97 on: August 10, 2017, 09:53:08 AM »
I should add as an update that what is left of the structural rebuild is:

install/glass motor mounts (wood is cut)

Install center section of floor over gas tank

glass over entire floor

cut transom keyhole



Offline fireman24mn

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Re: CVZ-18 hull rebuild has begun!
« Reply #98 on: August 10, 2017, 01:52:22 PM »
I bought a 383 and had it shipped to me my total cost with shipping was just under 3,300. It was a long block with intake, valve covers, oil pan, balancer, and timing cover.
I think this has become an addiction.


1977 CV-23 I/O Full Resto complete
1976 CV-16 V8 Resto in progress
1985 Pearson MotorYacht 43ft

Offline Scott in nh

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Re: CVZ-18 hull rebuild has begun!
« Reply #99 on: August 10, 2017, 02:01:57 PM »
I bought a 383 and had it shipped to me my total cost with shipping was just under 3,300. It was a long block with intake, valve covers, oil pan, balancer, and timing cover.

I've been following your build - beautiful and an inspiration to keep going!

I don't want to hurt my outdrive and my budget and time (not to mention skill set) for the entire project is probably 1/4 of yours, so a healthy 350 close to, but less than 300 HP is what I am after

I missed who built your motor and where you bought it?