4.3 engine failure

[garyzzz84]

hell room. a little history of my problem. last summer i caught a plastic bag around my out drive and over heated my 4.3 gl volvo penta on a 17.5se glastron 1998. had new rebuilt installed thru insurance. this moter lasted 7 hrs be for it started tapping and knocking on July 1st this year. another new rebuilt was installed July 27th. now have 17 hours on this one and it is tapping and knocking.. been told from different places could be remans were bored to tight. could be wrong cam for this boat and finally it could be a bad carb. im terrified to pay for another motor and it happen again. any one out there have suggestions. HELP

 

[Scott Danforth]

welcome aboard

do you have a remote oil filter? if so, is it plumbed correctly?

 

[alldodge]

do you have a remote oil filter? if so, is it plumbed correctly?

Yep, good call Scott

 

[Lou C]

ahh at this point of course make sure if there is a remote oil filter, it is installed right but I'd put in the difference $$ wise to get a new long block.

 

[garyzzz84]

hello guys. no it has the standard spin on oil filter on the block. i have been very careful watching my temp and oil pressure. all are great . this is a 4.3 GLPBYC. nothing fancy about it. original motor would do almost 60 mph with just me in it. was fast and scary. its running a 4 blade piranha prop, 15.2 x 22.8 These last two engines did not come any where close to this speed. The hull is totally clean as boat is pulled out every sunday when we leave cottage. top speed is 50_53 mph. the first new rebuild i was told 2 cylinders were scuffed , one each side. This engine sound seems to be coming from rear on only one side. i will try to down load a video i did of knock

 

[alldodge]

i have been very careful watching my temp and oil pressure. all are great .

The issue is if the lines were swapped (the in for the out) you will see good oil pressure, but the flow to the motor will be restricted.

Look at the filter adapter on the block, and make sure the center line going to the block adapter is labeled OUT on the filter adapter. Oil comes IN on the wide section and OUT on the center section

 

[garyzzz84]

Ill have shop have a look. this all came attached from reman company. one of largest in USA out of houston ADK or something like that

 

[Scott Danforth]

Also, make sure the block bypass valve is a 30psi unit and not an 11psi unit

 

[garyzzz84]

Thanks guys for your help. Has any one experienced a bad carb taking out a new motor. Possibly fuel wash. Boat started and ran smooth, no heavy gas fumes or boggieness . Idles smooth. This second reman motor is still warranty providing its not my fault. i have to pay to have it sent back to Huston from east coast Canada for them to tear apart and decide. This is the same carb off of my first motor that over heated. it ran like clock work for over 200 hrs. shipping charges will prob cost me more than having my original motor rebuilt.

 

[Scott Danforth]

Your fuel system can absolutely take out the next motor. Specifically if youre running lean and detonating

Fuel wash down is normally from a mechanical fuel pump with a ruptured diaphragm (you dont have a mechanical fuel pump), a leaking welsh plug from a rochester carb (which you shouldnt have) or a mis-wired fuel pump and a weak needle and seat. This you could have, however you would hear the fuel pump runnin when the motor is off, and it would be a biotch to get started and would run rough as he#

 

[garyzzz84]

Thanks Scott. i have an volvo electric fuel pump with the filter water seperator assembly attached at front of motor. The Carb is oem Holly 2 barrell. The engine broker who ordered this engine for me from ATK is trying to lay blame that its prob a bad carb that is causing engines to scuff pistons and walls. If so i wont get coverage. i asked him what caused the first rebuilt to fail and he said ATK wouldnt tell him. If they suspected it was a bad carb and did not relay that info to him or me that just bad business. soooo Peeevvvved.

 

[Scott Danforth]

Start with measuring your fuel pressure

take an oil sample, have it tested. The oil sample will tell you if you have fuel in your oil or not

 

[Bondo]

i have an volvo electric fuel pump with the filter water seperator assembly attached at front of motor.

Ayuh,..... Pull the filter, 'n examine it's Contents in a clear container, for anything but clean fresh gasoline,.....

With yer history, I'm with Scott, a lean condition, causin' detonation,....

 

[Lou C]

Well being a Volvo GL carb engine, the carb should be a Holley, and they are known to run rich at idle, who did the set up on the carb after the re man engines were installed? Did they make sure the floats were set right and adjust the idle mixture? For a rich running carb to ruin a motor that fast, it would have to been obvious, as in rough running, rough idle, black smoke out the exhaust
What about ignition timing?
Scuffed cylinders sounds more like less than great re-man quality control. But do as Scott says, an oil analysis will help in finding the cause.
I have always been somewhat suspicious of re-man engines, years back when I was on boatered.com I recall George Van Parys saying the only re-mans he would install were Mercury's because they stood behind their warrantee, the rest not so much.
When I need to re-power I think I'm going with a new GM marine V6 Vortec. Only want to do it once.

 

[alldodge]

bad carb that is causing engines to scuff pistons and walls.

Scored walls from wash out would also be seen and smelled in black smoke, rough idle and gas smell. Causes for scoring is things getting hot, rings not correctly installed. If motor should have been bored but was not and larger rings used, this can also cause issues.

As others mentioned, running lean can ruin a motor fast, but if this happened, there should also be pieces missing from the top of pistons, tuliped valves and scored walls (to much heat in the combustion chamber)

As for Merc remains, I have a buddies 454 MPI motor setting in the barn that was a Merc reman and had about 100 hours before it spun a bearing. It all comes down to the quality workmanship done

 

[garyzzz84]

thanks guys again for all the input. As far as i know the carb adjustments had not been touched . this carb was just removed from first engine that had 200 hrs on it and bolted to the first reman then to the second reman engine. I will be checking with the shop on Monday morning to verify this. There was never any rough idle, black smoke etc. I will get an oil sample checked and oil filter contents inspected

 

[Bondo]

and oil filter contents inspected

Ayuh,...... 'n the Fuel filter's contents,.....

 

[garyzzz84]

Hi Bondo. What should I be looking for in the fuel filter? I have a lot of questions to ask the shop tomorrow. ill keep you posted with their answers .

 

[Bondo]

Ayuh,..... Anything but clean fresh gasoline,......

 

[garyzzz84]

hello guys. just a quick up date . sent oil sample off to volvo penta today. as asked earlier the filter is not a remote , it attaches to lower right rear of block. im hoping to have timing chain cover removed to check cam serial # to verify if it is a marine cam. will let you know.