5.7 alpha one gearing/prop issue

[thannah84]

alright fellas...I recently bought a 95 proline 211wa and I can’t get it to plane right. It takes a good 45 seconds to minute to get it on plane. I have played with the trim of the outdrive, played with the trim tabs and the best is when the outdrive is all the way down and the trim tabs are all the way at now down. Now, the previous owner hit something with the outdrive and the insurance put a brand new outdrive on it, but it’s a 1.62 ratio. I can’t find anywhere where they should have had that ratio, everything I read says it should be a 1.47. So, I played with the prop, I went to the standard mercury 3 blade with a 17p and it made the problem even worse, but gained 2-3 mph at the top end. Currently it has a Michigan wheel 15x16p 4 blade. On Lake Erie in a descent chop it tops out at 4400 rpms and 28 mph. Where do I go next? Pull the trigger and get a 1.47 upper? Bigger trim tabs (currently have 9”x9”)? Stainless prop? Keep trying props. Engine runs flawlessly, I just feel like it’s a dog compared to other boats I ride on. For instance my buddy has a 5.0 alpha one in a bigger boat and he planes out great and does 28mph at 3700 rpms.

 

[achris]

.... it tops out at 4400 rpms and 28 mph. Where do I go next? ....

You can start with telling us what engine it is (serial number would be best). Different 5.7's have different WOT specs...

95Proline 211wa tells us nothing....

Chris......

 

[thannah84]

Serial Number is OC461300. I thought all SBC’s were 4400-4800 except for the 350MAG.

 

[Bt Doctur]

With a 14 x 19 you should be at your max rpm and flying across the water.You have another problem somewhere else

 

[AShipShow]

With a 14 x 19 you should be at your max rpm and flying across the water.You have another problem somewhere else

Do you trailer the boat? you might want to get it weighed to make sure you don't have a waterlogged boat that weighs 2000lbs more than its supposed to.

 

[thannah84]

I do trailer it. It doesn’t seem water logged. The scuppers are at the right height in the water so it doesn’t seem like it’s riding low, no listing etc. I thought this was a “no wood” construction and closed cell foam built boat so not sure where there would be water holding?

 

[wahlejim]

Closed cell foam is water resistant, not water proof. No boat that I have seem is "no wood" even though they are advertised as such. Weigh the boat for peace of mind. Using a prop slip calculator, 4400RPM at 28mph with a 16 pitch prop and 1.62 ratio you are sitting at 32 slip, which is awful. Something is dragging that hull or engine. with a 16 pitch prop that boat should be spinning at much higher RPM. A .15 ratio change will not have this much of an impact on results.

Here are some specs from proline for your year and model

 

[Howard Sterndrive]

I'd start with a compression test and make sure linkage opening carb all the way.

 

[Scott Danforth]

heavy boats and boats at elevations higher than 4500 feet get the 1.62:1 ratio with the V8's and its standard on the 4.3's that would have came in the boat

according to the Proline info, just the hull weighs 3100@ https://prolineboats.com/wp-content/...nformation.pdf

if that is the case, with motor, gear, etc you could be at 5500#

so weigh the boat
do a compression check
check the plugs (read them)

 

[Rick Stephens]

With a 5000 plus pound boat seems to me a 1.62:1 ratio would be a pure blessing. I'd stick with it. You swap to a 1.47 and it will be worse, not better. You have something else happening. Great advice from the brains.

 

[achris]

Serial Number is 0C461300. I thought all SBC’s were 4400-4800 except for the 350MAG.

Nope, some were 4200-4600, some 4600-5000....

And here's why we ask for serial numbers. Your hull is 1995, your engine is 1989, Model 457B100BS and your recommended revs are.... 4200-4600... (When you post in future, be sure to mention you have a 1989 engine, even though it's in a 1995 hull. In fact, we don't even need to know what the hull is. )

You're currently getting 4400, which is right in the middle of the range. If you're having problems with acceleration, then drop one size prop (2" LESS pitch)... But in that boat, with 260hp and 1.62 drive, that engine should be spinning its head off. Something else is at play here.

You need to check the engine condition. Start with a compression test. Also check the timing, and that the plug leads are all on, and on the right spark plugs. Also check that the throttle is opening up fully (throttle, not choke. The one at the bottom of the carb)...

As a comparison. My boat's only 270kg lighter, and I only have a 220hp V6 (same drive ratio) and I'm hitting 40 knots. You should be running at least 35 knots (not 24)...

Chris......

 

[Scott Danforth]

since proline only offered the 211WA with outboards and with a 4.3. having an older motor would mean the motor was swapped.

so.....weigh the boat (bet its heavy)
and do a compression test.... all cylinders should be between 130psi and 150psi. any cylinder above 150, question the gauge or look in the cylinder for water or oil.

 

[Bondo]

Ayuh,..... All I can add is,.... Bein' a trailer boat at 30-odd % prop slip,......

Crawl under it on the wagon with a 6" straight-edge, 'n check the keel line,.....
It should be straight for atleast 4" or more,.....
If you see air space 'tween the edge, 'n hull, it's grown a divot(hog), 'n will never plane out right,.....

 

[thannah84]

Well..not sure how accurate that serial number was. PO said he sparked off the motor after fueling at the fuel dock because he didn’t run blower. Assuming the cover that has the serial number got damaged as he did state this was the original motor but new outdrive. It’s there another location of serial number?

Lots of good advice here. A lot of checking I need to do. I guess I will add that this had a tune up as recent as 2016 (plugs, wires, cap, rotor) but don’t see where they did anything with the carb. (Have all the receipts for the past 10 years). An old timer told me today that it could be in the carb even though it runs good at the top end. Just not enough power at the low end. He mentioned accelerator pump, but still doesn’t add up to me? It doesn’t sputter or hesitate, just seems to bog and be slow to come up on plane and finally hit 4400rpms. It has a 4bbl Quadra jet.

 

[achris]

Well..not sure how accurate that serial number was. PO said he sparked off the motor after fueling at the fuel dock because he didn’t run blower. Assuming the cover that has the serial number got damaged as he did state this was the original motor but new outdrive. It’s there another location of serial number?

Yes, on a plate on the block just next to the starter motor.

Lots of good advice here. A lot of checking I need to do. I guess I will add that this had a tune up as recent as 2016 (plugs, wires, cap, rotor)

"As recently as 2016!" Tune up, and particularly oil and filter change is ANNUAL!

but don’t see where they did anything with the carb. (Have all the receipts for the past 10 years). An old timer told me today that it could be in the carb even though it runs good at the top end. Just not enough power at the low end. He mentioned accelerator pump, but still doesn’t add up to me? It doesn’t sputter or hesitate, just seems to bog and be slow to come up on plane and finally hit 4400rpms. It has a 4bbl Quadra jet.

Yes, lack of power at the low end will reduce the top end even though it's good at the top end... :facepalm:.. You do hear how contradictory that statement is?

Follow the good advice here, and leave the old timer to his steam engines. Accelerator pump has absolutley ZERO to do with the top end. But, those Q-Jet carbs can be very fiddly to set up properly. eg, the spring tension for the air valves is quite critical, and needs to be done EXACTLY as the book specs...

Chris......

 

[thannah84]

Yup. I planned on throwing new cap, rotor, plugs and wires on it when I winterized it. It’s cheap enough and a good piece of mind. Probably take the carb off this winter and have it rebuilt. I hear horror stories about these Rochester’s if you don’t get them right.

 

[thannah84]

Wanted to update. Fixed my issue. New cap, rotor, plugs, plug wires and she pops right out of the water now. Still have about the same top speed and rpms which I’m okay with. Cap and rotor had some green corrosion on it. Plugs had also seen better days.