Re: Alignment Tool
put grease on the end of your tool and slide it in the hole (god did i just say that) pull the tool out and look in the hole at the back of the coupler if you can c were the tool had left a mark on it from the tranferance of grease this should guve you so ideal of witch way you need to go. the bearing will move inside its housing and you can move it around with your tool some move easy and some you have to use some force to get it to move somtimes when you pull the drive off it moves the bearing. if you look it the alginment shaft hanging out of the boat you sould be able to tell witch way it needs to arte you get the bearing close the you can start on your mounts moving them up or down if it way off then you should c some sort of wear on the outdrive shaft and splines here is a pick of the bearing out of the boat and it tolerance ring1) here is a step by step on how to align
Start with outdrive DOWN , and shift in forward gear.
2)Step on left side blade and force downward (CCW).
3)Watch the engine pulleys when the prop turns.
4)If the engine turns, the coupler is usually good.
5)If the engine does not turn when the prop turns something is broken.
6)If propshaft does not turn with prop, the prop clutch is stripped..
7)If the shaft behind the engine doesn?t turn but the propshaft does your outdrive is broken.
8)If the prop and shaft turn and the shaft behind the motor, but not the engine, your coupler is broken.
9)Before replacement of the coupler, check the following.
10)Look across the boat transom and have a heavy person stand on outdrive and bounce.
11)If the transom flexes it will cause failure and must be repaired before the coupler is changed.
12)If the front motor mount is loose or if the pad where it sits is rotten, alignment will cause failure.
13)If these mounts and transom are good proceed with coupler change.
14)There are several possible couplers most are available aftermarket.
15)The im850 fits all Chevrolet with 3-1/2" bolt pattern on crankshaft.
16)The im598 fits all v-8 Fords.
17)Newer Chevrolet take the triangle coupler (small for 12-1/2 f/w large for 14" f/w).
18)If you do not know the size of the f/w, measure across two holes (10" or 11").
19)The im505 fits newer v-8 Chevrolet engines with 3" bolt pattern to avoid the triangle coupler.
20)The 224 C.I.D. Mercruiser uses two different couplers which are the early coupler or the late model coupler thru aftermarket.
21)When coupler is removed the reason for failure can be determined.
22)There are five possible failures.
23)Rubber in coupler broken in half (Struck under water object).
24)Splines internal in the coupler gone (lack of lube on splines long term) or bad rear height alignment (short term)
25)Rubber slipping in external shell (underwater object if old, possible flaw if new)
26)Rubber separated from core spline (hit underwater object if old) possible flaw if new.
27)Rubber melted (most common) poor alignment.
28)Only reason 25 or 26 have any chance for warranty and then only if part is new.
29)If melted and transom and mounts are good, Check alignment.
30)Alignment is the correct angle of the engine so the rubber in the coupler does not have to bend when the shaft from the engine is inserted through the gimbal bearing.< The rubber is suppused to turn the shaft but stay undisturbed when the shaft is inside. It is always easy to hit the rear opening of the coupler with the outdrive shaft, but the shaft mist go directly thru from there. Any slight elevation or drop in the front of the engine will cause the rubber insert to flex to allow the shaft inside. when the engine turns 1/2 turn the rubber flexes the opposite way. This flexing at 4000 rpm causes the rubber to heat untui it melts.
After the engine coupler is installed and the engine replaced the rear mount bolts are important for rear allignment. The metal washer goes on the bolt followed by the spacer. These three pieces go thru the engine mount from the top. In the space between the engine and the transom plate support tabs there should be two washers one fiber and one lockwasher which fit inside eachother with the bolt from above going thru into the hole in the tab. The nut goes on the bottom of the tab. This bolt must be tight before the allignment is checked.
Push an allignment bar through the gimbal bearing and into the engine coupler, tapping it to full depth. Hit the rear of the bar on the top and side with a large hammer to allign the bearing with shaft. Take the shaft and try to pull the bar in and out of the coupler with thumb and forfinger. If this is possible the allignment is correct. If the bar is hard to move in and out the allignment is out. Hang the motor front lifting ring on a hoist or come-along and loosten the front mount so the motor can fall further down than it started then have someone lift and lower the front of the engine until the bar slides easily, at this point lower the mount to support the engine at this height. Remove the hoist and recheck the bar. Fine tune the allignment by turning the mount nut for least resistance on the allignment bar. Good luck
) and look in and see the coupler... Adjust the engine up or down so it looks close to alignment... That is your starting point... You can get it pretty close visually...