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Since my oil pressure is on the way down....been think it's about time to rebuild my original 35yr old, 1400 hour 454's!
I know most of you guys all have the big money Hatt's with diesels....but have any of you done the project and have a "ballpark" cost?
Other than having marina pull the motors with the forklift.....planning on doing most of the work myself....even tho last motor I rebuilt was over 20 years ago!
Is it engines or gauges?
Are both engines displaying low oil pressure or one?....If one, I'd try reversing the sender wires to the gauges, between port and starboard and see if the readings are the same are before switching....could just be a guage or sender.
Are you burning oil...any smoke? Engines still turning up proper RPM and starting as normal??
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If you are doing it yourself - the cost to rebuild a 454 is not very high - should be able to do one for no more than 1500 bucks in parts pretty easily ASSUMING there is no damage to major components - block/heads/crank, etc. Otherwise it's just a standard rebuild - bearings/rings/valve job, etc.
Unless you have nothing better to do with your time I'd get a exchange long block and just swap your manifolds and parts. The last couple gas motors I put in my trucks were GM factory new crate motors. Their prices if you can get a discount are close to RB's and then u can sell the cores.
Is oil pressure fine when running? Run it till she blows!
Agreed. In my last boat, I installed a Jasper reman long block (350 ci). Ran flawlessly. Reman long blocks are in the $2-3 boat buck range. They come fully tested and with a guarantee.Quote:
Originally Posted by rsmith
If you go this route, make sure you match what you are replacing or else things that don't come with the long block may also need to be replaced.
Long block. It will cost less than doing it yourself.
BOTH gauges are showing low (18 to 20psi) running at 3k rpms. Haven't checked them otherwise yet. Not burning any oil. And not sure if they turn to proper rpm's cuz I don't run them past 3300.....Quote:
Originally Posted by REBrueckner
Something doesn't sound right. I would validate those readings with a known good mechanical gauge.
Give them the full exam, Compression , look at plugs to see how it is burning, leak down if you think there is an issue.
I agree with pulling OP sender and putting in new one and test with another gauge.
if they are Crusader model 350's and HE cooled then 1400 hours is not that bad.
Now if you want to have them perfect then balance and blue print and update with Edelbroch carbs and electronic distrubutors etc then get another 35yrs out of them. Balanced and blue printed is "free extra power" and will be better than long block.
Longblocks would be fine especially if you run only 40 hours a year. You can also drop in a small diesel ( I have a buddy at Yanmar that told me that have a drop in replacement for just a bit more than a gas engine price)
I'd sure be interested in that! Last time I spoke with the Yanmar Dealer...they wanted $75k for two 315hp w/gears installed. And that's waaaaaaaaaaaaaaaaaaaaay outta my budget!Quote:
Originally Posted by Boatsb
They are Chris Craft Marine Power 454's w/330HP.Quote:
Originally Posted by 67hat34c
Quote:
Originally Posted by ohiohatteras
At 3K RPM I bet they generate about 100 HP. Check your PM. I have an idea.
Not familiar with CC engine, dont know if they used the GM industrial block or not. Crusader used the GM Industrial block that has 4bolt main and some other more beefy stuff, little more hp @350.
I suspect yours are the automotive blocks with 2bolt mains and if so would go with long block.
I would not do anything until I ran a compression test. If that turns out OK. I would invest in new Edelbroch carbs, ( their great) electronic ignition, plugs, wires, larger flame arresters and let them fly. From what you say you don't run them hard. But with the new carbs, plugs, wires, ignitions and larger flame arresters your going to get a lot better fuel usage. Labor is the biggest cost to pull and rebuild. Your near Toledo call Motor rebuilders and see what they want to rebuild. They have done well with many of my friends. I also have an older friend in Point place that's all he does is rebuild marine engines. I would be more adpt to trust a local rebuild than an outside purchase should there be any problems.
BILL
Make sure the rebuilder knows how to do marine engine rebuilds. There are different rebuild kits ect.
1400 hours is entry level for these tough engines. We have 1400 on ours and they check out as new. I really am puzzled by your low oil preassure readings on BOTH engines. Those original AC gages are junk, but if they both read low, I suspect that your DC voltage is low. Those gages are actually re-labled volt meters. Do hook up a mechanical gage before you jump to any conclusions. Don't be afraid to run them at full throttle for a few minutes. You need to do that to make sure they are turning between 4100 and 4500 RPM. Try using 20W40 Shell Rotella oil also. They should not be ready for overhaul for another 1000 hours.
I fully agree with Maynard. Use mechanical gauges run compression check, if all is good run 'em for another 1,500 hours.
DC
It's now officially on my TO DO list for spring commissioning!Quote:
Originally Posted by DLCameron2
Thanks guys!
FWIW: Although they are good for finding an obvious problem like very low or no compression in a cylinder, I'm not a big fan of compression checks alone for engine health. From a useful information point of view, the compression check provides maybe 1/4 of the info you need and a LEAKDOWN test provides 3/4. Heck, you can pretty accurately tell an engine's condition with only a leakdown but you can't do that with only a compression check. Of course, the compression check should come first because if it shows one or more bad cyls, the engine has to come apart anyway and there's no reason to bother with the leakdown at that point.
Compression test can be misleading because carbon buildup on the piston/combustion chamber/valves can cause a compression reading to be even higher than specs. This makes one think that the engine is in REALLY good shape when actually it is not. A leakdown test will give you an accurate picture of what's really going on.
A search of "leakdown test" will find tons of articles describing the equipment/procedures. It takes a lot longer than a compression test and some additional equipment.
Mike if compression is even and not burning oil then can one assume rings are good? Leak down it a little tougher to do and equipment expensive or at least for a good set.
I've got my airplane in for its anual inspection right now,one of the main tests is the leakdown. They rate the cyls at a % based on 80 being 100% 80/60 is marginal . The test is good for finding leaking valve seats and cyl cracks since we're talking AL jugs. But the test is subject to the person doing it. You can move the prop back and forth and unseat the rings to make it look good or bad. Also a little oil in the cyls will bring the #up. And its all done cold. I think the cranking compression test tells more of the engine health but no one wants to stand next to a spinning prop.I think the leakdown is more of a diagnostic test to determine where the problem is coming from.
I would say that if the compression is within specs and there is no sign of oil burning then the ring/cyl wall condition is "good enough".
Normally, "within specs" for a compression test is no more than 10% variation between the high and low cylinder. For a good engine builder that spec is way too much but it IS the standard for factory service work.
I think if the engine is running, making good power, not burning oil, and giving no problems, then one should keep running it. But hey, we all have opinions.
Hours are better than sitting.