mx5cartalk.com

so i went out to the car today to do some maintenance, looks like she wasn't happy & didn't get enough attention lately. well it had been a while since she got a wash but i dismissed last weekends wash due to rain throughout the week..

leaked coolant onto the driveway i did find the source though. due to a hole in the secondary lower radiator hose (must of happened after i got home from work on friday), the one that connects from the metal pipe into the hose & then the engine.

so i've spoke to MotorMate (a store very similar to Repco/Sprint Auto) & they've ordered one in for me. but! it's a single piece lower radiator hose.

ok to use?

i'm not even sure why mazda didn't make it single piece originally. from what i can see it goes, radiator/lower radiator hose/this metal pipe thingy/2nd radiator hose/engine.

what on earth is that metal pipe for between the hoses?

also a lot of the oil has seem to of disappeared. i refilled it last weekend & when i checked today it was about 4 mm above the L mark on the dipstick.. something relevant to the coolant leak maybe? theres no new oil leak as far as i'm aware.

i put in Shell Helix Ultra 5w40 last oil change, had to use some of a 1L Castrol GTX2 bottle from Big W to fill up. certainly isn't as revvy but it'll have to do until next oil change where i'll try out this Mobil 1 & a magnetic sump plug.

i have replaced the other lower radiator hose last month. easy job. i bought an OEM one but maybe i will try a silicone one next time.

CORRECT ME IF I AM WRONG!

i reckon one long hose will be more expensive to replace. the metal pipe in the middle makes it more secure. do u know the rubber hoses will expand when the coolant gets hot. it will make hoses diameter bigger and slow coolant flow. hence less efficient cooling and power loss. the metal piece remove a weak point in the cooling system.

for the oil comsumption, have u check ur CAS for oil leak? what colour is ur smoke?

just checked the CAS, it does have some oil on the underside. spose i'll need to keep an eye on it now to see how quickly a leak spreads. i know the rocker cover leaks a bit, easy to clean the extractor side but the rear, front & intake side i can't really do anything about without disassembling things.

although last week i noticed a lil bit of oil around the passenger side bolt of the timing cover that i don't think i saw there before.. havn't seen any smoke lately, but about two weeks ago driving to work with a cold engine i had to mash the accelerator to get into a gap of the traffic & the puff of smoke from that was black.

interesting point about the expansion of the hoses. makes sense i guess for mazda to do what they did. i spose i could cut the single piece hose into two pieces.

hrmz, bummer. looks like i'll have to use public transport to get to work & back

whats wrong with the car now.. the smoke getting worse???

might want to go back to a tihicker oil next change. ive been told that the thinner oil leaks from gaps more easily than the thicker oil. helps slow down the oil leaks.

you might want to get some silicon grease and a new cam cover gasket. about $60-$70. its and easy thing to do... and i suggest you don't torque the cam bolts up to spec.... its scary tight.

well the coolant leak is fixed. the single piece rad hose i ordered turned out to be the 2nd one anyway. not exactly the same shape though but similar enough to be decently usable. i think the reason why it's catalogued (brand is Gates) as a single piece is because the same hose can be used for that 1st & 2nd part of the lower radiator section.

i didn't give it a trial fit to see for sure though but from looking in the engine bay i think it'd work in that 1st part.

spose the CAS is another thing to add to the list of things to do. well i'm nearly through it.

the smoke in my opinion is probably normal for an mx-5. i only ever see a smoke puff (black) whenever i really make use of the accelerator from a stand still or cruising pace.

last time when i posted a thread about it ages ago it was using crappy oil that could of also used a change since i had used a fuel injector cleaner (smoked a lot on a cold engine being revved to 2 grand under the carport). Castrol Protech, the stuff K-Mart Tyre & Auto use. only available to those in the auto trade. i spose demand isn't high enough for the consumer market, just as well since it's a terrible product.

i've learnt my lesson, don't go with these minor services where they use a crap cheapola oil. i now do the oil changes myself i'm happy to say, i never did that on my previous car.

Me wrote:do u know the rubber hoses will expand when the coolant gets hot. it will make hoses diameter bigger and slow coolant flow. hence less efficient cooling and power loss. the metal piece remove a weak point in the cooling system.

Errr how out of interest? Fluid flow is based off how much volume pump can flow. Given water is incompressible the flow is based of cross-sectional area of the pipe times the m/s flow rate. As the pipe expands the m/s flow rate drops but the cross-sectional area increase so the overal flow rate is the same.