First post to the Forum but have been reading How-To's and articles for years from this site and normally finding my questions not needing to be posted. I'm in a little bit of a bind in my situation since the power on my boat is from swap.
1973 Formula F-180
Alpha One MR (upper) and Pre-Alpha Lower
1986 Merc. 5.7l 350
The current Trim pump is an old square Prestolite pump which I have found to be High Pressure - Low Volume.
This weekend the motor took a turn for the worse and I am refusing to put another used one on and have the same thing happen to me. When researching the different style pumps there are the newer Low Pressure-High volume pumps which suggest are used on larger diameter trim cylinders and then they make a High Pressure-Low volume like I have now that uses smaller diameter hydraulic trim cylinders. My current pump when working was extremely slow from the 1/2 way to full up position. Most of the descriptions on different sites suggest I should have the Low-Pressure High Volume pump given my years of the outdrive. Is it possible I have the wrong pump now? Can I toss a pair of calipers on my trim cylinders or any sure sign which one I really need? What damage would I cause by using the wrong one? One site says run either since the pressure created is so close to the same. He had much faster trim response with the newer Low Pressure pumps. Another got into the physics of the trim cylinders themselves and the volume of fluid and never found a for sure answer. Any help appreciated before I drop some money into this.
Thanks!
1973 Formula F-180
Alpha One MR (upper) and Pre-Alpha Lower
1986 Merc. 5.7l 350
The current Trim pump is an old square Prestolite pump which I have found to be High Pressure - Low Volume.
This weekend the motor took a turn for the worse and I am refusing to put another used one on and have the same thing happen to me. When researching the different style pumps there are the newer Low Pressure-High volume pumps which suggest are used on larger diameter trim cylinders and then they make a High Pressure-Low volume like I have now that uses smaller diameter hydraulic trim cylinders. My current pump when working was extremely slow from the 1/2 way to full up position. Most of the descriptions on different sites suggest I should have the Low-Pressure High Volume pump given my years of the outdrive. Is it possible I have the wrong pump now? Can I toss a pair of calipers on my trim cylinders or any sure sign which one I really need? What damage would I cause by using the wrong one? One site says run either since the pressure created is so close to the same. He had much faster trim response with the newer Low Pressure pumps. Another got into the physics of the trim cylinders themselves and the volume of fluid and never found a for sure answer. Any help appreciated before I drop some money into this.
Thanks!
