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-   -   If you know you spun a bearing clap your hands...Clap clap (https://www.miataturbo.net/diy-turbo-discussion-14/if-you-know-you-spun-bearing-clap-your-hands-clap-clap-38311/)

sixshooter 08-25-2009 06:08 PM

Since you said the cam was also fucked due to starvation, I'd spend a minute figuring out what caused a lack of oil pressure to the entire engine before proceeding. Do the oil pump gears look good? Gauge was reading that you were making pressure or no? Did you run low on oil? Was it leaking or using oil causing you to run out?

If the same guy that built the motor is the one who proposed the theory about the debris, then maybe he's either a dumbass who doesn't understand how your engine lubricates itself, or he knows he fucked up on your build and is trying to steer you away from the real root cause that might point at him. Just an idea...

railz 08-26-2009 02:25 AM

You know what? when the loud knocking happened just after the bearing spun the oil pressure went to zero and stayed VERY low for a while and after i limped the car home.
The talk you have about the oil pump is worrying me because it is OE replacement from my local NAPA autoparts store

So whats this all about the oil pump?

the dumbass you speak of who buillt it was by the hands of me, first build so be easy T_T

aznDragonX 08-26-2009 02:43 AM

learn from your own mistake is not something you can buy...

magnamx-5 08-26-2009 03:03 AM

railz most likely you had a substandard spring in your pressure relief for the oil pump if it works for a while and quit or you installed the head gasket wrong and blocked the ports to the head, and the eventual presure build up did bad things not to mention the lack of splash and drip oiling from the lubers and head drains, becouse they come after the pressure gauge but before the head gasket. 2scoops of hooah did that to his first motor but luckily cuaght it before he threw a rod.

sixshooter 08-26-2009 08:53 AM

^ What he said. If you put the headgasket on backwards (and it looks just fine that way) you will not lubricate anything in the head and the blockage would probably hold the oil pressure relief spring open nearly constantly. I still think you would have oil pressure at the rods, unless the main bearings were installed upside down, but you would have heard rod knock very early on. What did you use for assembly lube?

Joe Perez 08-26-2009 09:12 AM


Originally Posted by Qckslvr (Post 446466)
I spun a bearing in my 1875cc vw once. Forgot to put the dowel pin in the rear main journal. Ruined the case halves, and a 8 pin balanced stroker crank. All happened in under 5 miles.

Oh yeah, the infamous dowel pins!

For those who never built an ACVW motor, the front and rear main bearings were one piece- IOW, a full circle, rather than split. To hold them in place, you had to put a dowel pin into a hole in one of the case halves before you dropped the crank/bearing assembly into it. Obviously you couldn't use plastigauge on these.

What was also seriously annoying is that the rear main bearing (which would be the pulley-side, not the flywheel-side, of the engine) was captivated by the cam drive gear, which you needed a shop press to get both on and off.

I spun a #3 rod bearing in my '71 SuperBeetle the same day I bought it. In fact, it was on the drive home from having picked it up. Major bummer that was... Turned out the second oil relief plunger (this was a dual-relief case) was stuck open. On the plus side, that was the excuse I needed to build up a high-compression 1776.

TravisR 08-26-2009 09:15 AM

High flow oil pump win? Boundary Engineering High Flow Oil Pump

neogenesis2004 08-26-2009 10:00 AM

Speaking oil pump gears. The ones I ordered from you site haven't arrived at my door yet.

TravisR 08-26-2009 11:04 AM

I called and checked on it, I he said he thinks can get it out today. We don't stock them they are all custom machined, and truly hand fitted so it takes a little longer.

wes65 08-26-2009 11:47 AM

You guys have just scared the shit out of me. I'm afraid that I put the head gasket on backwards. I didn't see any markings dictating which way it should be installed and iirc I could only get it to go on one way.

railz 08-26-2009 12:38 PM

Yes be very scared.

Im not sure if you guys have looked at the oil pump but it has a metal plug on it and for some reason mine was missing. i noticed this when after i got my motor running that there was oil mist collecting all over the engine bay. i dont remember if the hole was plugged when installed or if somehow the plug blew out but on the OEM pump it was there so i took the OEM pump took the plug out and put it in the new pump i got

if no one understands about what plug im talking about i can take pics to make things clearer?

Joe Perez 08-26-2009 01:27 PM

Sidebar, on the fancy oil pumps.

I just recently ordered a set of BE gears to go into Jessica's oil pump. As this will be a daily-driver / AutoX car, I bought the stock-sized ones, predicated on the fear that when the oil is cold, system pressure will be even higher than it is with a stock pump. I typically see oil pressures in the >90 PSI indicated range (the limit of my gauge) at 3,000 RPM on cold oil. I don't consider this to be particularly excessive RPM, and my concern is that with larger pump gears, trying to pump 25% more oil through a stock-sized relief valve, that I'd wind up rupturing an oil filter, blowing an oil line, etc.

Thoughts?

Qckslvr 08-26-2009 02:13 PM


Originally Posted by Joe Perez (Post 446746)
Oh yeah, the infamous dowel pins!

For those who never built an ACVW motor, the front and rear main bearings were one piece- IOW, a full circle, rather than split. To hold them in place, you had to put a dowel pin into a hole in one of the case halves before you dropped the crank/bearing assembly into it. Obviously you couldn't use plastigauge on these.

What was also seriously annoying is that the rear main bearing (which would be the pulley-side, not the flywheel-side, of the engine) was captivated by the cam drive gear, which you needed a shop press to get both on and off.

I spun a #3 rod bearing in my '71 SuperBeetle the same day I bought it. In fact, it was on the drive home from having picked it up. Major bummer that was... Turned out the second oil relief plunger (this was a dual-relief case) was stuck open. On the plus side, that was the excuse I needed to build up a high-compression 1776.

you didn't need a press to put the dist and cam gear on. Just a hot plate, get em good and hot and they dropped right on.

I also pinched a bearing in one. Got the case halves torqued, put my engine crank handle on and it was froze. :( When I split it sure enough the front main (flywheel) rotated just a hair and pinched.

You can have too much oil pressure. When I built my 455 olds for my jet boat I remember having a lengthy discussion on high volume pumps vs high pressure pumps. With too much pressure you start loosing lubricity. At least thats what the boys at Mondello Twister were telling me LOL.

TravisR 08-26-2009 02:14 PM

What oil filter/oil are you using? Matt who runs this pump has never given any feedback about severe over pressure. On my stock pump I have had the same thing, but that was with a cheap oil filter.

y8s 08-26-2009 02:28 PM


Originally Posted by TravisR (Post 446897)
What oil filter/oil are you using? Matt who runs this pump has never given any feedback about severe over pressure. On my stock pump I have had the same thing, but that was with a cheap oil filter.

Matt Andrews if anyone wants to ask me.


Joe P, what oil are you running to get 90 psi at 3k? stock is like 45-55 give or take at 3k warm.

Joe Perez 08-26-2009 02:30 PM


Originally Posted by TravisR (Post 446897)
What oil filter/oil are you using? Matt who runs this pump has never given any feedback about severe over pressure. On my stock pump I have had the same thing, but that was with a cheap oil filter.

Oil is Mobil1 0W40 synthetic, filter is a Mobil1 model M1-104 (standard fitment for Honda B-series engines) which has the same thread and O-ring as the miata, but the canister is maybe 1-2cm larger in both diameter and length.

And by cold, we're talking SoCal / Florida cold.



Originally Posted by Qckslvr (Post 446896)
you didn't need a press to put the dist and cam gear on. Just a hot plate, get em good and hot and they dropped right on.

I can maybe see the hotplate working for putting it on. Getting it off, not so much.

With my luck, I'd get the heated gear halfway into place and then get interrupted. :rolleyes:

M-Tuned 08-26-2009 02:31 PM


Originally Posted by railz (Post 444420)
i've gone WAY past my build budget so for rods im looking these. ETD is m-tuned right?

Mazda Miata 323 1.6 1.8 B BP H Beam Rod Rods:eBay Motors (item 190328220337 end time Aug-22-09 18:46:53 PDT)

They dont include the rod bolts but i still have them from the m-tuned rods

That is NOT ETD RACING or M-Tuned. That is some eBay company which has been copying ETD for years. Now they are even doing rods.

flier129 08-26-2009 05:30 PM

I can feel your pain, my first engine went out from laziness, second one went out from dirty assembly :(. Next engine will be assembled by a well known pro.


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