Compression Tests are Evil

Brother · 02:14 PM

I was at the auto hobby shop today changing the oil on the 914 and doing some other clean up tasks.

One of the mechanics came over to look at the car. He built a trike with a bus motor. I started the motor for him, and he thought it sounded wrong. He leans over and starts pulling plug wires on the distributor cap. On 2 of the cylinders there was no audible change to the sound of the motor. Oh crap. There was spark going to the wire. The plugs are new.

I pulled the number 2 and 4 plugs and they were black and sooty. The 1 and 3 plugs were clean. I cleaned everything and put them back.

Then I got a compression tester and ran it on all of the cylinders.

#1 - 100
#2 - 83
#3 - 85
#4 - 83

What the F?

Also, in the last few weeks, I have been getting backfires and pops under load around 2500-5500 RPM. It idles low cold. When it is warm, it idles around 1000 RPM. Also, it has a surge every 1-2 seconds. You can hear it and see it on the tachometer.

Do I have a broken ring, cracked head, or do I just need a valve job.

Nostril Cheese · 05-11-2007, 02:54 PM

put a some oil in the cylinders via the spark plug holes, turn it over with the coil disconnected. If the compression readings go up, you have worn rings. If not, it could be valves.

Brother · 05-11-2007, 07:11 PM

I should do a valve job first.

Do I have to dump all of the oil to do a valve job?

NOTASIX · 05-13-2007, 08:46 AM

Do a LEAK DOWN test! Compression tests are virtually worthless for diagnosing what is actually the problem!

Brother · 02:07 PM

I'll do a valve job next and try to check the fuel pressure.

The carbs probably need to go to ACE. They are probably my number one problem.

I just got an oil analysis report from Blackstone.

Iron - 18
Copper - 11
Lead - 20
Sodium - 18

Way too high. This was after only 500 miles. Fuel was also nearly 2% of the mixture which is way too high.

Maybe I'll start with the carbs, fuel pressure, and valve job. Maybe I can get some more life out of the motor before I rebuild it.

Brother · 05-26-2007, 02:05 PM

Lets just assume that this engine is toast. What would you do?

Re-ring, hone, and check things out hoping that will be all? $500+ (guess)

2056 engine kit, new cam, new carbs? $5000+

2270 engine kit, new cam, new carbs? $7,000+

2270 engine kit, new cam, RAT EFI, fuel pump and lines? $10,000+

I'll probably need a new exhaust with the 2270 kits. I have SSI's and a bursch muffler. Would I be making huge compromises by keeping my current setup with any of these kits? What are the hidden costs and extras that I might end up paying for?

NOTASIX · 05-26-2007, 04:59 PM

Quote:

Originally posted by Brother
Lets just assume that this engine is toast. What would you do?

Re-ring, hone, and check things out hoping that will be all? $500+ (guess)

2056 engine kit, new cam, new carbs? $5000+

2270 engine kit, new cam, new carbs? $7,000+

2270 engine kit, new cam, RAT EFI, fuel pump and lines? $10,000+

I'll probably need a new exhaust with the 2270 kits. I have SSI's and a bursch muffler. Would I be making huge compromises by keeping my current setup with any of these kits? What are the hidden costs and extras that I might end up paying for?

There are no hidden costs for the internals of the engine, my kit replaces everything that was previously inside your case with all new RAT parts.. The only cost variable is if your case is servicable, or if you do the machine work to fit the parts- at maximum you'll incur an extra 165.00 if we do all the machine work on the case..

I have no issues personally taking the time to help you outline the cost and all associated parts before an engine kit purchase- I want you to have a great experience because having properly built MassIVe engines on the road is what gets more built and makes you happy....

We do this dozens of time per year and have all the bases covered.

Brother · 05-26-2007, 07:20 PM

Thanks, Jake. I'll give you a call. I have to think about a couple of things first so that I don't waste someone's time on the phone.

RJMII · 05-27-2007, 07:40 PM

Quote:

[i]

I have no issues personally taking the time to help you outline the cost and all associated parts before an engine kit purchase- I want you to have a great experience.... and makes you happy....

We do this dozens of time per year and have all the bases covered. [/B]

Now THAT is service!

NOTASIX · 05-28-2007, 04:47 PM

Quote:

Originally posted by RJMII
Now THAT is service!

We have no issue offering pre-sale consulting to potential clients.. Thats because we want everything to be totally up front from inclusions, options to understanding of the risks and time involved- the worst thing for us is the impulse buyer because they are never pleased in general.. We want to make sure that everything is "known" prior to taking a dollar...

Brother,
Email me at
productdevelopment@aircooledtechnology.com and we'll set up a Wednesday evening phone appointment that works around your schedule...

Brother · 05-29-2007, 07:17 PM

Email sent, Jake.

NOTASIX · 05-30-2007, 07:02 PM

I didn't see one.. Try it again, junk filter might have grabbed it.

Brother · 05-30-2007, 07:09 PM

Sent again.

Brother · 06-03-2007, 10:13 PM

I just want to let everyone know about a Jake Raby phone consultation. Jake is absolutely an incredible guy. He spent about 1.5+ hours on the phone with me telling me about all my combo options. Of course, this was at 12-1:30 am his time. He didn't spend time trying to up-sell me. In fact, he didn't sell me anything. This is nothing but discussion and education.

Jake isn't holding anything back on IV dimension. He is giving the same great information to his customers as he gives on the podcast.

Well, I'll let everyone know when I get an engine kit. It might not be real soon, but it will happen. I finished the wiring on my battery relocation today. The starter and electrical system is better, but the engine still sucks. It still has heinous backfires, low idle, and generally crappy running.

Here is my dream sheet after my talk with Jake.

2270 Torquer Engine Kit
RAT SDS EFI with direct fire ignition add on.
Tangerine EVO II 1 3/4" headers and muffler
Setrab oil cooler
New Fuel Lines
CHT Instruments
4 way 914 gauge

The price tag is high, but this combo would be like turning your guitar amp up to 11. It certainly is not much compared to 911 prices.

The real question now is do I save for the engine kit first or do all the body work and repaint the car first and then do the engine?

I can't drive the car until the engine is fixed. So if I can't find a problem to fix, the car is a paperweight until the engine is fixed.

NOTASIX · 06-04-2007, 03:04 AM

Paul,
Thanks for the compliments.

I try VERY HARD to ensure that anyone wanting to buy an engine kit has the proper information up front, both before we receive a dollar from them and before they even take it from their pocket.

The way we do things is different than other shops, just like our components and engines are. Being in the Military you can probably understand my methods better as well as the structure they are built from.

I look forward to your kit purchase and answering any other questions/concerns that you may have before, during and after the kit process.