Notices
Series I Trouble Shooting This is the place to learn more about or discuss any issues you're having with your RX-8

Low vacuum, low compression, bad MPG

Thread Tools
 
Search this Thread
 
Rate Thread
 
Old 05-05-2010, 09:05 PM
  #26  
Registered User
 
enamel's Avatar
 
Join Date: Dec 2008
Posts: 26
Likes: 0
Received 0 Likes on 0 Posts
Hi guys,

Some bad news.

I called the dealership today, and I spoke with the rep, and then the manager.

The representative told me that: "there is nothing wrong with your engine. The compression test results come back as normal. Our diagnostic testing indicates that these numbers (6.7, 6.7, 6.8) are normal. You tell us that 6.9 is the lowest threshold, but where are you getting these numbers from? Also, our readings are at certain rpms. At different rpms, these numbers will be different. I can't switch out your engine, because the computer (not our interpretation), says that it passes the compression test"

After argueing with him I spoke to the manager who says this:

"look, its not up to me whether or not I get to switch out your engine. The normal readings are between 680, and 830. Your readings for the first rotor was 680. And the readings for the 2nd rotor was normal".

I then argued with him, stating that the first guy told me that it was 6.7, 6.7, 6.8.

He then stated: "look, I'm not disputing that your readings are lower than 6.9. I know what you are saying. I will talk to mazda tomorrow, and see. I will phone you back".


I'm finding that this is so hard and difficult to deal with these people.
Old 05-05-2010, 09:07 PM
  #27  
Registered User
 
enamel's Avatar
 
Join Date: Dec 2008
Posts: 26
Likes: 0
Received 0 Likes on 0 Posts
the manager or rep also mentioned to me that these readings were at 255 rpm.

Thanks guys for any support/feedback.
Old 05-05-2010, 11:10 PM
  #28  
Administrator
 
zoom44's Avatar
 
Join Date: Jul 2002
Location: portland oregon
Posts: 21,958
Received 115 Likes on 88 Posts
he's correct. it matters what the results are together with the rpms . your initial readings dont include RPMs so aren't complete. But he did tell you something important that you seemed to have missed. the low end for a rotor is 680. Yours was tested by them at 6 80. So your motor is very low on compression in one rotor. it'd be a good time to do the engine cleaning and you should also check with them that they are putting this on record for you so that in a year or two when its below 680 they/you have records of the previous tests.
Old 05-08-2010, 08:43 AM
  #29  
Registered User
 
enamel's Avatar
 
Join Date: Dec 2008
Posts: 26
Likes: 0
Received 0 Likes on 0 Posts
Hi guys,

I want to give an update to the situation:

The manager of mazda phoned me back and said the following:

"We redid the compression test. basically we performed it wrong last time. This time we did it when the engine was warm and the temperature was appropriate. The results were all about 800 for both rotors. We all did the engine cleaning beforehand just to make sure that the results would be accurate - free of charge. We did the compression test wrong the last time. We have everything documented here.

Now all you need is the spark plugs and filter replacement - all for 340.00."

I guess if this is the truth, then the whole problem has been taken care of.

There is no way they could falsify this data is there?
Old 10-01-2010, 04:50 PM
  #30  
kevin@rotaryresurrection
iTrader: (3)
 
RotaryResurrection's Avatar
 
Join Date: Feb 2005
Location: east of Knoxville, TN
Posts: 1,415
Likes: 0
Received 57 Likes on 35 Posts
Originally Posted by BigTurbo74
Price or an overhaul varies like you said earlier. The important thing to gauge value is to figure out what parts are being replaced. For instance, I believe rotary resurrection is a popular choice because Kevin will replace what's needed to get you back on the road and do it at a low price. On the other hand I think a shop like turblown.net uses new rotor housings in all of their builds to ensure long service life. New housings will definitely bump the price up but in many people's eyes it's worth it. Just call around for details.
Sorry to bump an old thread, but it is not *that* old and it is still relevant. I wanted to clear up info about my procedures for those who may find this in a search and use it in the future to evaluate their options.

My basic rebuild priced lower than any other rebuilder in north america (that I am aware of) is basically just that...a basic refresh with most major components being reused and mostly new seals etc. being new replacements and a few seals/springs being reused.

Why would anyone reuse seals, springs, and core components, you ask? Is it because I am being cheap, or worrying about making a couple hundred extra bucks off a customer? NO.

Mazda or other part suppliers make most of the money off of rebuilds and parts. They are the ones who keep jacking up the prices. Even for a basic refresh/rebuild, the OEM seals etc. that I use add up to about $900-1000. I only charge $1550 for a rebuild, so you can clearly see what I am making for my 30 hours of rebuild labor/time, plus misc. shop materials to clean and inspect the engine during the rebuild.

Parts get reused because they cost so damn much to replace. Over the years I've identified parts that are major wear items and others that are minor wear items or do not really wear at all, and this is how I've determined what to reuse and what to replace as a matter of course. Obviously each engine core is different and sometimes abnormal wear or damage dictates further part replacement (and cost).

The biggest myth I've fought for the last 10 years of doing rotary builds is that I build cheap engines and don't replace everything that should be. Well, honestly if you look at the list of what I replace in each build (clearly listed on my site) and compare it to what some of the higher priced builders use, you'll see I'm pretty much replacing everything that they are. That is, if you can even GET the other builders to tell you exactly what is being reused vs replaced. Yet some of them still charge more, and still get a reputation for using better parts than I do. This includes mazda, whose engines are often called "new" but instead are simply their version of a rebuild with some used part content; how much is used and how much is new, who knows?

Now there are some builders who are more picky and will simply not build an engine reusing much of anything other than rotors, irons, gears, shaft, and misc. hardware. They FORCE you to buy new rotor housings, all new rotor seals/springs, plus pay their labor, whether or not some of your original parts were reuseable. Maybe they don't think you as the customer should have that choice, or maybe they think you are not smart enough to make the choice yourself.

Technically they are right...new parts are great and will build a better, more reliable engine. But, forcing everyone to build an all-new-part engine (and pay the bill) is kind of like taking your car to a garage for a clutch, and being forced to replace the flywheel, transmission, motor mounts, and driveshaft, even though there is not much wrong with those other parts...because hey, new parts are better than used, right? Better not take any chances!

Now, don't take this the wrong way, but just about anyone can be trained to build an engine from all new parts and get good results...they probably have 65 year old grandmothers in japan building rx8 blocks right now. I feel it takes as much or more skill to judge what can be reused and still get good results, than to simply slap together a bunch of new parts, force your customer to pay double the price, and call it a day.

These builders who use more new parts (and charge accordingly) are generally regarded as being "better" or "higher quality" builders than myself. That is fine, but a not-so-subtle point of logic is escaping those who draw this conclusion: have you ever considered that you could <gasp> *pay me extra to replace even more used parts with new parts* and get the exact same build offered elsewhere? Just because my base rebuild is priced a certain way and includes a certain group of new parts, does not mean that is ALL I am willing to do. Of course if you want to step up to a better build with more new parts I am willing to accomodate you...of course you will carry the burden of the extra part cost.

It all comes down to cost in the end. People get on the internet and talk a big **** about "doing it right the first time", "building for reliability", "I want to build an engine out of all new parts", "money is no object", "I promised myself I wouldn't compromise on this build", blah blah blah. Then when you put pen to paper and show them what it will cost, they backpedal very quickly. "Oh wow, I didnt realize...", "well, what if we leave off this, and this...how much then" until finally we arrive right back at where we started, with my basic rebuild and base price. And suddenly they decide, that's not so bad after all.

Unlike other builders, I give the customer the choice to decide what will be used in their engine. I provide detailed pictures upon teardown of their core and explain any issues, wear, or damage, and give options for part replacement new, used, etc. and offer my opinion and judgement on the matter. They decide what to use and what to replace. When the engine is built they get more pictures of the cleaned parts that were selected for the build, and of assembly of the block. There are few other builders who do this, most won't even tell you what parts are being used vs new in your build.

Several times yearly I tear apart cores which have been supposedly previously rebuilt, ported, 3mm seals, whatever...and come to find out half of it wasn't done or was poorly done. They never believe me until I show them pictures. They had no idea of what they had the whole time. Earlier this year a customer sent me an FD block from a single turbo that he had personally paid 4 grand to be built by a very high end (fruity) builder in the PAC NW that everybody sackrides as building the best engines. He'd paid for 3mm apex seals and a large streetport...standard build for a single turbo FD. Upon disassembly I find that he actually had a very small streetport (rough at that) and 2mm seals. Dude was not happy, especially since the 3mm seals could have saved the engine (if they had been there to begin with). He was able to have me re-rebuild it, port it larger and smoother, do the 3mm seal conversion, replace the damaged parts from being blown, and still came out to less than 75% of what he paid for the original block from that big name professional builder.

Also, take the time to look around and see which builders are giving out support to the community...answering questions, giving opinions, maintaining a presence on the internet forums etc. and being a part of the community. Most builders want no part of this or any other forum. If a builder is not here when you have questions via posts or pm, why do they deserve your business when you need an engine? Look around, there are about three builders on this forum helping you. Myself, BHR, mazmart. But, people still sackride some of these other builders who otherwise want no part of the rx8 community. Sadly, there are probably some people using my engine removal and engine teardown to bare block writeups to prepare their engines to send to other builders.

Last edited by RotaryResurrection; 10-01-2010 at 04:56 PM.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
drebbrnator
Series I Trouble Shooting
11
12-27-2018 07:02 PM
uZu
New Member Forum
13
12-30-2015 12:35 PM
dafiltafish
New Member Forum
1
08-21-2015 06:56 PM
CMRine04
New Member Forum
15
07-29-2015 02:07 PM
dbarber
Series I Trouble Shooting
14
07-25-2015 01:34 PM



You have already rated this thread Rating: Thread Rating: 0 votes,  average.

Quick Reply: Low vacuum, low compression, bad MPG



All times are GMT -5. The time now is 07:48 PM.