Mercruiser 3.7L Lifter Problem

[imported_River Rat]

Just finished a complete rebuild of my 85 model 3.7L.
All went together well and started and ran fine on the hose. Went for a shake down cruise and all was fine for about an hour. Then while coming off plane it devoloped a "rattle" in the top end, Oil pressure OK, temp OK,. Idled a few minutes back to the ramp, got it home and discovered that there are 3 lifters that are colasped. Push rods OK, rockers OK. Valves don't appear to be sticking, will confirm with a compression test tonight.
Any idea's on what might have caused this?
Can the colasped lifter be "revived" or do they need to be replaced?
Comments / Questins please.

 

[lilmandavis]

Re: Mercruiser 3.7L Lifter Problem

did you do a pump up before starting this engine? (prime the oil with a drill motor to get pressure?) another thing is to much oil will foam up and cause oil infused with air bubbles, that wont be able to build pressure. so the lifters collapse.

 

[imported_River Rat]

Re: Mercruiser 3.7L Lifter Problem

did you do a pump up before starting this engine? (prime the oil with a drill motor to get pressure?) another thing is to much oil will foam up and cause oil infused with air bubbles, that wont be able to build pressure. so the lifters collapse.

Yes I did a pump up and built oil pressue B4 initial start up. Oil level was and is OK.

 

[imported_River Rat]

Re: Mercruiser 3.7L Lifter Problem

Latest Update: Pulled the lifters tonight and found (2) that are trashed. They are worn so bad that the overall length of the lifter is about 150 thousands short of all of the rest of them. What gives, this is from about 1 hours run time? What about my new cam? What should I do next?
By the way, both the cam and lifters were new from Mercruiser

 

[Don S]

Re: Mercruiser 3.7L Lifter Problem

Those pushrods come in different lengths. Since this engine was rebuilt, are you sure you had the correct size pushrods installed for correct adjustment?
Also, on the 3.7's did you get an alignment tool for the oil pump? if not, you could end up breaking that hex rod attaching the oil pump to the distributor so it will turn. It's been the downfall of many a 3.7L rebuild by an unexperienced rebuilder without a Merc manual.

 

[lilmandavis]

Re: Mercruiser 3.7L Lifter Problem

well its time for a tear down... there is no way around having those shaving in your rod and main bearings. and that is hard steel. time for a rebuild buddy. MAKE sure that you have your crank cut down. somewhere you lost oil pressure, the valves werent set right or whatever.. but it must be found in order to not have it happen again to a rebuilt engine....
melling oil pump!

 

[Bondo]

Re: Mercruiser 3.7L Lifter Problem

Latest Update: Pulled the lifters tonight and found (2) that are trashed. They are worn so bad that the overall length of the lifter is about 150 thousands short of all of the rest of them. What gives, this is from about 1 hours run time? What about my new cam? What should I do next?
By the way, both the cam and lifters were new from Mercruiser

Did you Run In the New Cam,+ Lifters,..??..

Without a proper Break-in,....... You've Probably Wiped Out the Lifters, And the Cam............

 

[imported_River Rat]

Re: Mercruiser 3.7L Lifter Problem

I did run the cam and lifters in.(1500 RPM for 15 minutes)
I did use an assembly lube on the cam and lifters.
I did use an oil pump alignment tool.
I did check the push rod length per the Merc manual
How is the oil delivered to the cam/lifters?
I agree, its going to have to come back out and come apart.

 

[calwldlif]

Re: Mercruiser 3.7L Lifter Problem

Galley plugs?