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Jayc
01-25-2008, 08:43 AM
Hi guys,

Adding a heater on my 84 S&S. Plan to take the hot water from the inlet manifold and then put the water back into the engine via the top fitting on the water pump.

Does this sound right? If so what are the threads on the block and pump so I can get some hose barbs?

TMCNo1
01-25-2008, 09:26 AM
First check with a MC dealer then, www.skidim.com (http://www.skidim.com) and either one can advise you as to where to connect, what to use to make it work or there may be instructions in the kit you buy or a contact # for questions about their system.

JLeuck64
01-25-2008, 09:56 AM
Take the fittings off the engine and stuff them in your pocket. When you get to your local hardware store they can help you identify the size fittings you will need.

As I recall....

An old 81 351 I had many moons ago I installed a heater and that kit tapped into the sending unit near the thermostat housing. The kit came with an adapter that allowed the temp sending unit and the hose barb both to share the same location. Maybe you could make something similar???

There is a drain plug located on the elbow of the recirculating pump (engine water pump) inlet that I used to install the hose barb. The engine water pump does an ok job of pulling water through the heater core above idle, but you will lose heat during extended periods of idling. SkiDim sells a clever, yet spendy, little fitting that lets you re-locate that hose to the inlet side of the raw water pump. Folks around here say they work pretty good at boosting heat during idle.

Send us pics when you get her figured out!

Jayc
01-25-2008, 12:17 PM
Cheers guys. Hoped to find out the threads so I could get the barbs in advance but will most likely just stick the temp sender and drain in my pocket and go to the hardware store.

When I fitted a heater to a mercruiser 350 I had to get a T piece to allow the use of a temp sender and barb at the same time but I'm sure my indmar equiped 190 had both a heater and temp sender thread on the inlet manifold.

I've got the Y pipe for the heater on my Maxum as heat was always low at idle. The indmar 351w i had before never had the problem with low heat at idle. Perhaps the ford pushes more water at idle than the GM or more likely is the heater circuit length on the 190 was 1/4 the length as on the maxum.

Off to the hardware store tomorrow then!

uawaterskier
01-25-2008, 12:33 PM
Cheers guys. Hoped to find out the threads so I could get the barbs in advance but will most likely just stick the temp sender and drain in my pocket and go to the hardware store.

When I fitted a heater to a mercruiser 350 I had to get a T piece to allow the use of a temp sender and barb at the same time but I'm sure my indmar equiped 190 had both a heater and temp sender thread on the inlet manifold.

I've got the Y pipe for the heater on my Maxum as heat was always low at idle. The indmar 351w i had before never had the problem with low heat at idle. Perhaps the ford pushes more water at idle than the GM or more likely is the heater circuit length on the 190 was 1/4 the length as on the maxum.

Off to the hardware store tomorrow then!dont go to a Lowes or Home Depot. Try finding an Ace or True Value, people who actually know hardware

stuartmcnair
01-25-2008, 12:59 PM
go to a plumbing supply store...

Jayc
01-25-2008, 01:25 PM
No chance of going to a Home Depot, I'm in the UK :)