| Author |
Message |
    
Annie Blide
New member
Username: stcroixmtn
Post Number: 1
Registered: 10-2009
| | Posted on Tuesday, October 20, 2009 - 11:08 pm: | 
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Marvin, if you are there..you seem to be an expert on 671's. I am looking at a 1984 Post Sport fisher in MN!!!The engines are 671 TIB's, with approx 2900 hours each. The boat is in dry dock,due to an early fall we cannot do a sea trial. The turbos were replaced in 2003. What could one expect on these 671's before they need a major overhaul? Approx cost on MOH? And suggestions? I have heard that a tech could access the pistons and rings thru a port in the engines to check condition, is that true? Thanks! |
MARVIN PIERCE
Advanced Member
Username: marv
Post Number: 333
Registered: 09-2001
| | Posted on Wednesday, October 21, 2009 - 01:06 am: |
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yes do have the pisto,rings,&liner inspected thru air box covers.pull oil sample for testing. as for time to o/h mabey 2000 more hrs,you can tell more after ring inspection.air, oil & fuel maints.as for cost to rebuild r&r labor + rrebuild 15-20,000 each. |
Annie Blide
New member
Username: stcroixmtn
Post Number: 2
Registered: 10-2009
| | Posted on Wednesday, October 21, 2009 - 09:53 pm: |
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Thank you Marvin for your advice! I really appreciate it. We will have this done! |
Annie Blide
New member
Username: stcroixmtn
Post Number: 3
Registered: 10-2009
| | Posted on Wednesday, November 04, 2009 - 04:44 pm: |
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What should be included in a MOH and must it be done out of boat?To increase the longitivity of the rebuilt engines should I detune them to 385 HP? Are the 671TI to small for a Post 46' if the intent is not to fish far offshore?Thanks to anyone who can answer these questions! |
Annie Blide
Member
Username: stcroixmtn
Post Number: 4
Registered: 10-2009
| | Posted on Wednesday, November 04, 2009 - 05:39 pm: |
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In reference to the last post, how many hours of labor per engine and approximate parts cost to rebuild a 671ti? I believe that everyyone should be able to make a profit on their work but would like to keep the rebuilder honest. Thanks again! |
Jimmy Graves
Member
Username: jimg4652
Post Number: 46
Registered: 11-2008
| | Posted on Wednesday, November 04, 2009 - 09:24 pm: |
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Major Overhaul: New cylinder kits (pistons, piston rings, cylinder liners; if rods are good they are reused) new main, rod, camshaft, and balance shaft bearings; new oil pump; new/rebuilt blower and turbo; oil cooler pressure tested/replaced; crankshaft removed/checked/cleaned/polished; aftercooler pressure tested/replaced; new/rebuilt cylinder head; new injectors; cylinder block hot-tanked, cleaned and pressure tested; new/rebuilt fuel pump; new/rebuilt water pump; gear train inspected; exhaust manifold cleaned; camshaft inspected; governor inspected; blower drive inspected/replaced; governor drive inspected/replaced and all new gaskets and fuel/coolant hoses. Also, I'd recommend going to a new-style fuel rack (if you have the old style) The old style takes a screwdriver to adjust the rack; there are two screws you turn. With the new style, you loosen the lock nut, turn the screw, and lock it down with the nut. On the new style, each injector is independent of each other. If one injector sticks the engine will start smoking/knocking. On the old style rack, if one injector sticks wide open, ALL the injectors stick wide open. Then the engine runs away and blows up. It's just a little extra insurance to have a new-style rack installed.
Marvin is accurate with his $15-$20K/each overhaul estimate. The engines should be pulled to do a major overhaul.
You can, however, perform an in-frame overhaul if you have enough room to do so. I don't know how your engine room is configured, so I can't tell you if it would be easier/more cost efficient to go ahead and remove the engines. I can tell you though, if I were the mechanic I would want to remove the engines. (Although mechanics will have varying opinions) I can do a lot better job with the engine out in the open on a stand and the job would be MUCH easier on my end. But I don't know how much it would cost for the crane service to remove the engines......that could be a deciding factor for you. Plus when re-installing the engines, it makes for a good excuse to re-align the engine to the gearbox which might get rid of any vibrations you may have experienced before (If the engines were out of alignment)
If you detune the engines to 385HP, yes you will get a few more hours out of them....maybe up to 7-8K hours depending on how well you take care of the engines.
Now whether 770 total horsepower will be enough for your boat, I couldn't tell you. I know our 800HP towboats can easily push a couple of barges...and I imagine our towboats are MUCH heavier than your boat. But our 800 horse towboats are lucky if they make 6-7 knots even by themselves....
Hope this helped. |
Annie Blide
Member
Username: stcroixmtn
Post Number: 5
Registered: 10-2009
| | Posted on Thursday, November 05, 2009 - 10:03 am: |
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Jimmy,
Thank you so much, that is a wealth of information that will surly help us make an informed decision.
Ann |
Annie Blide
Member
Username: stcroixmtn
Post Number: 6
Registered: 10-2009
| | Posted on Thursday, November 05, 2009 - 02:46 pm: |
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Anyone, checking all options regarding 671 TI's.
Is there anyone that sells remanufactured 671's complete , crated and with any warranty? Thoughts on only an upper overhaul on engines with 2800 hours and appproximate cost of doing them in boat?
Thanks again to all. |
MARVIN PIERCE
Advanced Member
Username: marv
Post Number: 334
Registered: 09-2001
| | Posted on Thursday, November 05, 2009 - 07:02 pm: |
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try pacific power products 800-882-3860
richfeild washington |
Jimmy Graves
Member
Username: jimg4652
Post Number: 47
Registered: 11-2008
| | Posted on Thursday, November 05, 2009 - 10:32 pm: |
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You can do a short overhaul and be good for a few thousand hours. We did one on a crew boat with 6-71 Naturals about 2 years ago. Replaced cylinder head, injectors, cylinder kits, rod bearings and blower. Haven't had a problem yet.
I'd guess about $5-6K per engine. |
