The original heat exchangers in my 98 Mack were a bit long in the tooth and I wanted to upgrade from a half to full system thereby integrating the exhaust manifolds. The original PCM system located the engine heat exchanger under the starboard exhaust manifold making engine alignment nearly impossible so relocation was also part of the plan.
I'll start with the final result!
I started with the exhaust manifolds and risers. The PCM manifolds did not have a provision for full system cooling, only half system. I looked over the common designs and narrowed my list to Mercruiser or Marine Power style manifolds, Mercruiser was eliminated due to the proximity of the scupper "gutters", it looked like spark plug replacement would be a PITA. I purchased Barr's version of the Marine Power/Indmar manifolds and 4" risers from Marine Engine Parts ( CHV-1_83 and 20-0100). Installation went smoothly, the bolts cleared the gutter with enough room for a ratchet and deep socket. Stainless separator plates and gaskets were installed to isolate the risers from the glycol, fit and finish were very good. Barr casts its manifolds here in the USA.
Next on the list was the thermostat housing and water outlet. I decided on a Mercruiser style, front mount, heat exchanger that provides much better access. The Mercruiser complete thermostat housing was nearly $400.00. Sierra sells the dual water outlet top for about $40, so I whittled out a copy of the lower from a chunk of 6061.
Mounting the heat exchanger was next, I used the vertical Vortec intake manifold bolts. A few spacers, aluminum angle and tubing, and voila!
The engine heat exchanger was supplied by Mr Cool #MFH-5399. Gear and engine oil cooler was also replaced, supplied by Marine Engine Parts.
This is the Mercruiser design that I used as a template:
www.marineengine.com
I ran the engine on the garden hose for about an hour and the temps look good with no obvious hot spots. The exhaust hose is remarkably cool near the riser, the outlet design is superior to the PCM risers and has a "water fall" like introduction of the raw water into the exhaust stream. All I need now is a nice window for a sea trial, but it looks like the wind will be up through the weekend.
I'll start with the final result!
I started with the exhaust manifolds and risers. The PCM manifolds did not have a provision for full system cooling, only half system. I looked over the common designs and narrowed my list to Mercruiser or Marine Power style manifolds, Mercruiser was eliminated due to the proximity of the scupper "gutters", it looked like spark plug replacement would be a PITA. I purchased Barr's version of the Marine Power/Indmar manifolds and 4" risers from Marine Engine Parts ( CHV-1_83 and 20-0100). Installation went smoothly, the bolts cleared the gutter with enough room for a ratchet and deep socket. Stainless separator plates and gaskets were installed to isolate the risers from the glycol, fit and finish were very good. Barr casts its manifolds here in the USA.
Next on the list was the thermostat housing and water outlet. I decided on a Mercruiser style, front mount, heat exchanger that provides much better access. The Mercruiser complete thermostat housing was nearly $400.00. Sierra sells the dual water outlet top for about $40, so I whittled out a copy of the lower from a chunk of 6061.
Mounting the heat exchanger was next, I used the vertical Vortec intake manifold bolts. A few spacers, aluminum angle and tubing, and voila!
The engine heat exchanger was supplied by Mr Cool #MFH-5399. Gear and engine oil cooler was also replaced, supplied by Marine Engine Parts.
This is the Mercruiser design that I used as a template:
Mercury Marine Exhaust / Cooling Systems & Extension Kits Closed Cooling System (91036A1 / A5 / A8) Parts
Mercury Marine exhaust / cooling systems and extension kits closed cooling system(91036a1 / a5 / a8) parts. Buy a genuine Mercury Quicksilver or aftermarket part.
I ran the engine on the garden hose for about an hour and the temps look good with no obvious hot spots. The exhaust hose is remarkably cool near the riser, the outlet design is superior to the PCM risers and has a "water fall" like introduction of the raw water into the exhaust stream. All I need now is a nice window for a sea trial, but it looks like the wind will be up through the weekend.
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