Michigan Motorz review: HGE Aluminum Manifolds and Risers

This whole expensive disaster started in February of 2014. I had used Michigan Motorz a few times before and thought they were a good solid company that stood behind the products they sold. I have a 33 foot Sea Ray with twin 7.4 Horizon Mercruisers. The boat has only 600 hours on it and has been professionally maintained its entire life. It was time to change out the manifolds and risers so ordered 2 full sets of HGE aluminum manifolds and risers as a set from Michigan Motorz. The kit came with bolts and gaskets. My boat is kept in the Connecticut River near Hartford so it was not going to be run in salt water. I had the manifolds and risers professionally installed and were happy that now the boat was about 100 pounds lighter and the manifolds put off less heat.

Then the trouble started. In November of 2015 I was putting the boat up for the winter and was shocked when I drained the oil on the starboard engine. It was cloudy and light colored. I knew what that meant and immediately had the mechanics check out the engine. After a few days the report came back, the manifold on the port side had failed due to deterioration and it appears the starboard side was also starting to fail. I had them pull the manifolds from the Port engine, same deterioration in the same place. I called Michigan Motors and explained the issue and the findings. They asked that both sets of manifolds and risers be sent to them so they could send them back to HGE for analyses and they would get back to me. I said I would send them one set as it seemed suspect they would need both sets. At this point I was getting worried. I sent the first set to them and they said they must have the second set before going ahead. I reluctantly sent them the second set. At this point I received the report of the damage to the boat. Both heads on the starboard engine were damaged badly by water intrusion and the port was starting to go. I had the marina write a complete report on the condition of the engines including past service etc.

I was not getting much feedback from Michigan Motors at this time and started to get frustrated. It took threatening them with a lawyer to even get a response form the owner "Phil" . I made sure most of our correspondence was via email so I would have a record. Phil assured me they would help me out and they were just awaiting the report from HGE. After a few conversations I felt a little better. In the mean time I asked the mechanics at my marina what the cause of such a manifold failure might be. They said it appeared to be a combination of poor casting and electrolysis. I kept wondering how this could be. The manifolds were installed using the bolts and the gaskets that Michigan Motors sent. The engines are in 100% working order and have not had any issues.

Then I got a huge shock, the response from Phil at Michigan Motors:

"All of the 9011A and 4354A HGE Exhaust manifolds have been Inspected and check by the manufacture HGE. They have determined that there is no Issue with the casting. They are declining the warranty claim.
There are many reasons for water intruded into the engine. One of the reasons may be due to improper riser installation or the bolts was not re-torqued after initial startup of the engine.
They notice there are severe electrolysis corrosion at the exhaust ports of the manifolds. It suggests that electrical system of the engine was not grounded properly."

This is simply not the case I told Phil and now the estimates on the damage and repairs were climbing into thousands of dollars. Only the manifolds had a deterioration issue that the rest of the engine was fine, the grounds were solid on both engines. Basically Michigan Motorz had decided not to honor their own warranty or help with the problem. I was now forced to get a lawyer involved which is in process now. I have asked repeatedly for my manifolds and risers to be returned and Michigan Motors refuses to do so and will not respond. It is my belief they know that if the manifold make it to court they will lose. Also during my research I found this warning from HGE that was not included with the manifolds I purchased from Michigan Motors:

https://www.manifoldwarehouse.com/mes/techinfo/AluminumManifoldNotice20120308.pdf

This warning is not specified in the original Ebay auction or the documentation on Michigan Motors site. I believe they knew there might be issues and sold me the parts anyway. I now have over $10, 000.00 in repairs and I am sure it will be much more in lawyers if I decide to go forward. I have all of the email correspondence, marine records and reports for anyone interested. I have evidence and pictures.