1991 431A-DP Engine alignment?

Author Message   Steve Kline New member Username: y2kvette Post Number: 1 Registered: 07-2009 Posted on Friday, July 17, 2009 - 09:01 pm:    1991 Chaparral with Volvo-Penta 431A-DP (4.3L Duoprop) I need to confirm that this engine/outdrive does not have any means of engine alignment due to there not being a gimbal bearing like the later I/O’s and other manufacturers. It seems to have a flexible plate somewhat like the flex-plate between a car engine and automatic transmission torque converter. See this link: http://www.volvopentastore.com/CONNECTING_COMPONENTS_DRIVE_SP_A_SP_A1_SP_A2_DP_A _DP_A1_DP_A2/dm/cart_id.127657359--session_id.643363086--store_id.366--view_id.3 14305 and this link, item 22: http://www.volvopentastore.com/CRANKSHAFT_AND_RELATED_PARTS_430A/dm/cart_id.3577 36370--session_id.504071515--store_id.366--view_id.314333 I need to repair the motor mount platform by just removing the motor mount and bracket on one side at a time while supporting the engine from the top with a chain hoist and the bottom with some 2x6’s under the pan. The bell housing appears to be directly bolted to the out drive by a clamping ring (#72 in the first link). Therefore it appears to be a non-movable connection to the outdrive? Comments? Anyone really been there on this era system? Thanks for the help, Steve   Ricardo E. Advanced Member Username: ricardomarine_vp Post Number: 407 Registered: 03-2009 Posted on Friday, July 17, 2009 - 10:55 pm:    Steve, there is an alignment between engine and drive, but it is fixed via the engineering and design of the flywheel cover, primary drive shaft and the connection to the transom shield. We can not change it's relationship up to the point of the U joint shaft yoke. **There is a required minor adjustment during initial engine installation only. The engine uses a regular flywheel like a auto/truck using a standard transmission. No flex plate like an automatic trans. The part attached to the flywheel is a "Drive Coupler" (# 22 on your second schematic) and it uses the Borg Warner internal splines for what is called a "Primary Drive Shaft" (item # 85 in your first schematic). If you support the engine while you change this, you should be OK. **If concerned, refer to your Volvo Penta "OEM manual" for initial engine installation and set up. There is a procedure for triangulating from three flat spots...... three each the "Flywheel Cover" and three each on the "transom shield". When the space between all six flat areas is equal, you are within specs. (Read your OEM manual and it will makes sense to you.) You'll be fine. For what it's worth, and IMOO here; I'd say favor a little lift type pre-load on the mounts......, rather than a loose fit that could allow the engine to drop down some. When under power, if there is any flex in the transom....., an engine that is slightly higher is favorable over one that me be lower.   Steve Kline New member Username: y2kvette Post Number: 2 Registered: 07-2009 Posted on Friday, July 17, 2009 - 11:36 pm:    Ricardo, Thank you so much for your expert advice. You have obviously been there before. You have to admit that the "regular flywheel" looks very much like a flexible link (even more flexible than a flexplate in a car, considering the triangular shape design). I fully expected to put a little lift pre-load on the engine and then support it from below the pan in the effort to not move the motor very much or allow it to drop any at all. Again, Thanks for your expert advice and allowing me a part of your day. You are a real professional. Steve   Ricardo E. Advanced Member Username: ricardomarine_vp Post Number: 409 Registered: 03-2009 Posted on Friday, July 17, 2009 - 11:44 pm:    Steve, are you confusing the flywheel w/ the drive coupler? The drive coupler sort of ressembles a clutch disc with no friction material on it. It bolts directly to the flywheel, appsosed to being compressed via an automotive type pressure plate. And.... you are certainly welcome. Always glad to help if I can. .   Steve Kline New member Username: y2kvette Post Number: 3 Registered: 07-2009 Posted on Saturday, July 18, 2009 - 12:15 am:    I understand that about the drive coupler. But the triangular shape still looks like it has some flex capabilities. Of course, I have not seen one, it may be of very heavy material. Thanks again. Is this what we non-party guys do on Friday nites? :-)) Steve   Ricardo E. Advanced Member Username: ricardomarine_vp Post Number: 410 Registered: 03-2009 Posted on Saturday, July 18, 2009 - 01:21 am:    I'm too old to party any more! So yeah!

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