unusual block

[rock]

Going thru some parts and pieces and found an unusual block. Dated 1-91 and marked with a single F as opposed to the normal FF. It also has a couple unique features such as a 4 bolt main and it looks like the center main oiler has been moved. Oil pump was never machined or drilled nor was the fuel pump area finished. 2.5 Unpainted block, relief notches in sleeves, 7 petal front, and exhaust ported. I originally built this block with Wiseco pistons and since this was before I started doing my own boring and before I knew about needing extra clearance the bores were way too tight. Motor ran great for about 4 or 5 hours before the pistons started dragging well before break in period was complete. Has anyone seen a block like this.

Rock

[David - WI]

I know it just came up not long ago... try here, and then later in this thread, too: https://www.screamandfly.com/showthr...86#post3241686

To my understanding the 1991 "F" was the original 7 petal 200.

[Merc 2.5]

My buddy has a block with the single f but its painted , was curious also

Ya its him ( Smalltownbassin)

It has single f and is set up just like a normal ff or ee block , but I think it has the better chest than ee , 5 pedal etc

[HStream1]

Randy the F coded block was only made 1 year 1991 it was the first year of the 2.5 and also had a 7 peddle front half as well as other unique features. In that its not painted its most likely a LakeX test Block. Or one that someone back Doored from mercury. I had one and it was a Great Platform. Sold it to a Kid on my Hydrostream. It was February. It dodnt have Thermostats as i had done the washer conversion. i told him DO NOT Take that boat out unless you install thermostats. Water temp was like 34/36 degs. He didnt listen and Cold seized the motor in about 45 seconds.

Going thru some parts and pieces and found an unusual block. Dated 1-91 and marked with a single F as opposed to the normal FF. It also has a couple unique features such as a 4 bolt main and it looks like the center main oiler has been moved. Oil pump was never machined or drilled nor was the fuel pump area finished. 2.5 Unpainted block, relief notches in sleeves, 7 petal front, and exhaust ported. I originally built this block with Wiseco pistons and since this was before I started doing my own boring and before I knew about needing extra clearance the bores were way too tight. Motor ran great for about 4 or 5 hours before the pistons started dragging well before break in period was complete. Has anyone seen a block like this.

Rock

[rock]

In that its not painted its most likely a LakeX test Block..

Bud that is what I was told when I acquired it. Didn't believe it cuz I have heard enough stories over the years. Looks like at least one sleeve won't clean up sufficiently and bottom two crankcase cover bolts came out with iffy threads so it will need repaired. It's too bad cuz block has had a lot of work and money invested in it. Maybe one day I will get James Perry to make me some special sleeves and see what it's got. Sure was strong before it puked. Hope you are doing well.

Rock

[Capt.Insane-o]

I have a couple 2.5 z blocks from the lake yet.

[Michael J Giesler]

That will be one strong motor after James works on it

[Merc 2.5]

So does anyone know bout the single f motor painted?

[tabme]

I have a True 1991 original Black F motor-EFI-7 pedal front. I never ran it/purchased new pistons from Capt. Insane-o about 6 months to do a rebuild on it just too many projects going on now. I have read there is nothing special about them except for the 7 pedal front but very restricted in the exhaust.

[Capt.Insane-o]

I have a True 1991 original Black F motor-EFI-7 pedal front. I never ran it/purchased new pistons from Capt. Insane-o about 6 months to do a rebuild on it just too many projects going on now. I have read there is nothing special about them except for the 7 pedal front but very restricted in the exhaust.

Before you put that together send it to someone and have the exhaust chest cut to a 225 pro max and the dumps opened up.

[tabme]

Thanks Capt. yes that will be one of the mods i will do once i jump in. Thank you again for the deal on the the pistons they are Truly New.

[fasterbass]

91 was the first year of the 2.5 and the motor was a bottom guided crank and rods. You can still use top guided rods on it

[tabme]

Thank you --Fasterbass The pistons i purchased from Capt. insane-o came mounted on rods-Bottom guided. I am working on too many motor at once rite now,putting the 91 on the back burner.

[Smalltownbassin]

So does anyone know bout the single f motor painted?

UPS says James just got the block today so we can see what his thoughts are on it. Its definately not a '91 though. Date stamp in the block is '01. Someone just posted one on FB the other day with the same question. It's another 4/5 petal "F" painted black. Sounds like the one described here is a legit '91.