Oil Cooler

n2rav4

Member
:
Mazda 5
I have a 2007 Mazda 5 Touring. Local garage says oil is leaking from gasket on oil cooler. Called 1 Mazda dealer, they say this model does not have an oil cooler. Called 2 mazda dealer, they say gasket not available, must purchase entire cooler at about $400.

The oil is leaking from a module located above where the oil filter is housed...is this an oil cooler? Does anyone know if gaskets/O-rings are available?
 
OK, 1st off, oil coolers are basically radiators for oil, and usually, they are in fact dual-core (tri-core with a transmission fluid cooler) radiators that can be found behind the grille. Otherwise they are secondary radiators located right in front of the main radiator, like the AC condensor is. Since you stated that the leak is right above the oil filter, that is not in any way able to be an oil cooler, as the point of a cooler is to reduce the temperature, and locating it attached to or inside the engine block will not cool anything. IDK if there are oil cooler lines in a Mazda5, and I don't have the car @ home w/me to pop under the body to look for cooler lines. But even if there was an oil cooler (unusual in a non-heavy-duty setting) there would be rubber hoses running from the engine block to the cooler just like small radiator hoses, and those usually do not need gaskets where they connect. I think it is time to question your local garage. They may be padding their bottom line. One thing about the auto repair industry: it takes a beating in the winter. No work to be had, so if someone comes in, they may be tempted to "inflate" the work needed to ensure they can make payroll, pay rent and keep the lights on. Or, a good shop would have those under control by putting away summer profits for the lean winter months.
 
thaxman, don't confuse fluid-to-fluid coolers for air-to-fluid coolers. Our vehicle has an AT (fluid-to-fluid) cooler, and I'm pretty sure I saw some coolant lines under there running to the oil filter housing. I'll confirm, but it won't be until I do the next oil change.
 
Well, its been 5 days, so I'm not sure out new member is going to check back in anyway. If I can remember 60 min from now, I'll look under my car when I get home. The hard part is remembering....
 
Taken from another forum, here's what you need to look for...

drainzb3.jpg
 
Ummm, isn't that a tranny cooler junction?

I looked from the top yesterday, and I did see some coolant lines running from the backside of the engine (tranny side) down toward the oil filter, but I didn't poke around. Since I have an MT, I know they weren't tranny cooler lines. Pretty unique how the block has the the heater hoses and radiator top hose coming out of the back of the block instead of near the pump. I say that assuming the pump is belt-driven and therefore must be on the front of the block where the lower hose comes in.
 
Yea, that's the tranny cooler. I was just trying to iterate the existence of the fluid-to-fluid cooler. I believe the oil cooler is similar.

BTW, 'gasket maker' would be perfectly acceptable in this situation. But I find it hard to believe that there is not replacement gasket for such a part.
 
Copied from another forum:
Oil cooler seal

1. Drain oil.
2. Remove oil filter
3. Remove oil cooler splash guard (metal guard on top of oil cooler)
4. Remove bolt holding in oil cooler (large bolt viewable once you remove the oil filter).
5. Remove cooler.

Replace oil cooler gasket with a gasket removed from an oil filter - it is about the same size.

This process should be an hour or so. Then reattach everything and put oil back in.

Really only expense is the gasket (buy a SuperTech filter if you don't have one)

2006Mazda5OilCoolerOverview.jpg
 
Has anyone performed this repair and does it really work? The reason that I would like to know is, I am about to perform the oil filter conversion along with the oil filter relocation and I have been warned against damaging the oil cooler gasket.
 
2006-2010 Mazda 5, L4/2.3L Oil Leaks at Oil Cooler Gasket. FIXED ! ! !

FIXED !!! OIL LEAKS FIXED !!!!
OK, Mazda 5, 2.3L oil is leaking at Oil Cooler gasket. Without right seals we can not stop the oil leaks. Do not use silicone or try to modify with similar gaskets because you will waste your time. Oil still leaking. Need to use:
1/. Oil Filter Stand Gasket (Part#LF02-14-342) (Flat thin rectangular shape)
2/. Oil Cooler Gasket (Part#LF8X-14-702) (2 O ring one big 1 small, connect together with a straight line. Like steering wheel)
The 1/. Oil Filter Stand Gasket you can buy at the dealer but 2/. Oil Cooler Gasket is not available. If you are interest to buy this 2/. Oil Cooler Gasket, drop me a contact inquiry at www.asiaautocare.com
I am very sure you will save $429.64 for the Oil Cooler (Part# LF6W-14-700A) which you don't have to buy. and oil will stop leaking.
 
Crrection about previous post.

FIXED !!! OIL LEAKS FIXED !!!!
OK, Mazda 5, 2.3L oil is leaking at Oil Cooler gasket. Without right seals we can not stop the oil leaks. Do not use silicone or try to modify with similar gaskets because you will waste your time. Oil still leaking. Need to use:
1/. Oil Filter Stand Gasket (Part#LF02-14-342) (Flat thin rectangular shape)
2/. Oil Cooler Gasket (Part#LF8X-14-702) (2 O ring one big 1 small, connect together with a straight line. Like steering wheel)
The 1/. Oil Filter Stand Gasket you can buy at the dealer but 2/. Oil Cooler Gasket is not available. If you are interest to buy this 2/. Oil Cooler Gasket, drop me a contact inquiry at www.asiaautocare.com
I am very sure you will save $429.64 for the Oil Cooler (Part# LF6W-14-700A) which you don't have to buy. and oil will stop leaking.
 
Well, the above is my post I posted earlier. I made mistake. I thought I got the right gasket. For those who found the Oil Cooler Gasket (Part#LF8X-14-702) (2 O ring one big 1 small, connect together with a straight line. Like steering wheel) selling in eBay. This will not be the right one.(the gasket is thinner than the original one)
Up to this time, I have to say gasket is not available.
 
It was really difficult to combine all of the info I found on different forums, websites about this topic, so I wanted to share a few things that I learned in the process of repairing (rather than replacing) my oil cooler. I have a 2009 Mazda 5 Sport with 78k miles. The oil cooler started leaking (Black, older design) between the oil cooler and the oil filter housing, as is common for this FoMoCo design and has been detailed in this thread.

As discussed, the dealer will only replace the entire unit with the newer design (silver) unit. My Mazda dealer here quoted me $480 for the part and labor to swap it out. I replaced the gasket in about 4 hours (could be done faster had I had all of the needed info in one place already) and for $13 plus a quart of oil and 1 gallon of engine coolant.

I ordered an oil cooler replacement gasket part at Amazon for $13.02 (this is the replacement gasket for the older black Oil cooler design)
https://www.amazon.com/dp/ (commissions earned)

There is a set of service manuals circulating online that was apparently leaked from a 2005 draft service manual, and is helpful, but not entirely correct for newer Mazda 5's since they switched at some point from the screw-on filter to the cartridge filter design, and the service manual is for the screw-on filter design. That is located here:

http://www.mediafire.com/file/wgev1ww9dc1c27g/Mazda5_WM.zip

It is worth looking at, but not exactly correct for newer Mazda 5 Models.

For re-assembling the oil cooler after installing the new gasket, torquing the unit back together properly is supposedly very important. Here are the torque specifications I found for reassembling the oil cooler: 25.1-29.5 ft lbs.

When re-attaching the unit I also never was able to find the torque specifications for re-torquing the unit to the Engine block, but found that it's important not to tighten too much or to get anything in the screw holes when re-attaching the unit. This is all I've found on that matter, but apparently got mine assembled sufficiently because it hasn't leaked in a month since doing it.

https://www.mazdas247.com/forum/sho...rque-values-for-oil-cooler-gasket-replacement

Additionally, there is a series of 3 YouTube videos where a guy actually repairs the gasket himself. These were actually quite helpful (although assumed a lot of technical knowledge I didn't have!) - Note about those videos, I did NOT install the gasket solution he recommended between the engine block and the oil cooler (nor did I on the old gasket, since I replaced the old gasket with the $13 Amazon one rather than repairing it.)

Video 1:
https://www.youtube.com/watch?v=s3Yx3rFnMuc&list=PLMLlmUSfWO5-EdidQ9LI1ZMG4gkEeqrrx

Video 2:
https://www.youtube.com/watch?v=glhk_RQTH8k

Video 3:
https://www.youtube.com/watch?v=YO9mgpotcik

Disconnecting the Oil Sending Unit was a BEAR! I had to rotate the unit to get to the back of it to remove the clip, and wouldn't have known to do that except I found this detailed writeup on replacing the oil sending unit (see pp. 7-8 of this PDF) which helped me to figure out how to get it detached.

https://cdn.shopify.com/s/files/1/0420/1017/files/DM_Oil_Pressure_Sensor_Adapter.pdf

A couple of more points: it is not needed to drain the entire oil pan before doing this install. Just drain only the oil filter oil through the bottom of the oil filter housing and then you will have less waste and only need to replace about 1 quart of oil instead of all of it. I drained only the oil filter housing and was fine. I only lost 3/4 quart of oil in the install.

Secondly: You should probably play it safe and drain all of the coolant from the radiator. I did not, and had quite a mess. I instead plugged the two coolant hoses when I disconnected them from the oil cooler. But I still lost nearly a gallon of coolant in the process, and if I had it to do again would have just drained the entire system first. I plugged the hoses with rubber bands and cellophane, but it wasn't a pretty solution!

Hope that is helpful to someone. It wasn't easy, but was really satisfying to see it work and have saved over $400. ($100/hour for my time; I guess that was worth it).
 
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