Miata Engine

[montgom]

I want to build an Exocet with my son. I am looking for a donor car. It appears that many folks buy really high mileage Miatas and seem to have no concerns about the engine durability. So, are Miata motors "bullet proof"? Would I be better off with a 30K miles Miata for more money versus a 130K Miata for less money? Miata motor rebuilds don't look cheap, so I tend to be drawn to the Miata with 30K miles versus the Miatas with 130K miles on the odometer to avoid engine repairs which will eat up any money saved in buying the 130K miles Miata. Does that make sense? Spend more on the 30K mile Miata and avoid the engine repairs that come with a 130K miles Miata engine/tranny/etc.

Thank you for your help.

[Stiggy]

Lower mileage is of course the best choice but remember that those engines appear to go on forever. My latest demo car has done 217,000 miles. I have not replaced any bushes, ball joints, pads or discs or even the timing belt. The engine looks tatty but could be cleaned up externally. The rubber suspension bushes look tired but are not shot so they do not need replacement. The MX5 based kits can be built at very low costs or be completely rebuilt as required or desired. The choice is yours. The builder is always going to feel more confident if every crucial component is replaced or refurbished. The screaming engine you hear in the attached clip still has the old oil and even the filter! 95 miles per hour, old shocks/suspension, hands off the wheel, not recommended but it feels and drives like a new car.

[johnp]

Couldn't resist playing with that!   (I'll understand if you delete this)

[montgom]

Sept 30, 2014 10:05:08 GMT Stiggy said:

Lower mileage is of course the best choice but remember that those engines appear to go on forever. My latest demo car has done 217,000 miles. I have not replaced any bushes, ball joints, pads or discs or even the timing belt. The engine looks tatty but could be cleaned up externally. The rubber suspension bushes look tired but are not shot so they do not need replacement. The MX5 based kits can be built at very low costs or be completely rebuilt as required or desired. The choice is yours. The builder is always going to feel more confident if every crucial component is replaced or refurbished. The screaming engine you hear in the attached clip still has the old oil and even the filter! 95 miles per hour, old shocks/suspension, hands off the wheel, not recommended but it feels and drives like a new car.

[montgom]

Thank you! Appreciate the help.

[gwnwar]

The MX5 engine is built to last.. change the oil and filter and coolant you are good to go.. weakest parts are the plug wires, and clutch slave cly. If the timing belt breaks it is a non interference engine.. pistons won't hit the valves.. '89-'91 1/2 had short crankshafts some problems with the crank key and keyway.. If you live in the UK I would be looking for a donor with the least amount of rust on the under side. This will same money and alot of time in the build.. Jump on in the water is fine..

[alr]

Anybody out there know of a good way to bypass the heater core and run the coolant hose from supply back to rear engine connection.

My only thought so far was to use a "U" shaped hose. I saw where the 2002 Ford Windstar heater hose to tee-2 looks promising.

Ron

[gwnwar]

Looping is the easy way..Go to your parts store with size tubing and tell them what you need..preformed with a 180 deg bend. they may let you got look through the hoses they have.. FYI supply is from the back of the head return down side in metal tube.. Remember there is an "O" ring at end of tube were it goes into the water pump.. Other may chime in with a make and number on the hose they used..

[montgom]

Oct 1, 2014 4:41:59 GMT gwnwar said:

The MX5 engine is built to last.. change the oil and filter and coolant you are good to go.. weakest parts are the plug wires, and clutch slave cly. If the timing belt breaks it is a non interference engine.. pistons won't hit the valves.. '89-'91 1/2 had short crankshafts some problems with the crank key and keyway.. If you live in the UK I would be looking for a donor with the least amount of rust on the under side. This will same money and alot of time in the build.. Jump on in the water is fine..

I have my donor car. 1994 Miata with LSD and five speed. Minimal corrosion as it was not driven in the slat and snow.

[gwnwar]

1994 1.8 is a good engine.. It had the most HP of any NA car.. Also last to have a real oil pressure gauge..
You might want to change the timing belt and pulleys and water pump and the CAS "O" ring.
If you haven't already go to miata.net forum forum.miata.net/vb/index.php
Lots of good info in the Garage Section, FAQ, and forum its self..
Here are a couple of sites for wiring and info..
www.mellens.net/mazda/

www.miataforumz.com/miata-wiring.php

Good luck on your build post pics.. Ask questions.. Start a thread on it in Exocet section make sure your donor year and engine size is in your profile and on all threads.. That makes it easier to help trouble shoot problems..

[montgom]

Thanks. I will change the timing belt, water pump and CAS O ring along with front main seal (little leak). And it does have a real oil gauge!!!!!

[colin]

I purchased the FM rebuild kit. This will be the second engine I'm rebuilding, the first we purchased each part as needed so I'm really looking forward to just having all the parts already in hand this time around. Well worth the extra cost in my opinion. Also, you will have a lot more faith in your engine if you have taken it all the way apart and put it back together after checking everything out.