Actron CP7828 Professional Compression Tester with Storage Pouch

by Actron

Product Features

• Includes adapters for 10mm, 12mm, 14mm, 14mm long reach, and 18mm standard spark plug threads
• Storage pouch keeps parts organized and repair kit includes valves and rubber O-rings
• Bourdon tube provides accurate readings and has 2-1/2 professional gauge
• Heavy-duty rubber boot protects gauge
• 1-year warranty

Product Details

• Product Dimensions: 1.5 x 12 x 5 inches
• Shipping Weight: 1.4 pounds (View shipping rates and policies)
• Shipping: This item is also available for shipping to select countries outside the U.S.
• ASIN: B00020BM28
• Item model number: CP7828
• Average Customer Review: 4.1 out of 5 stars  See all reviews (28 customer reviews)
• Amazon Best Sellers Rank: #748 in Automotive (See Top 100 in Automotive)
  • #1 in Automotive > Tools & Equipment > Diagnostic & Test Tools > Pressure & Vacuum Testers

Product Description

This compression tester measures cylinder compression to accurately diagnose engine leaks from rings, burnt valves and blown head gasket. This tester has a quick disconnect coupler that separates the hose from the gauge for faster, easier connections to the engine. Also included are a push-button side release valve that allows repeated testing without disconnecting. It is compatible with all standard spark plug threads. It includes a comprehensive user manual with illustrated step-by-step automotive test procedures and has 1 year warranty.

Customer Reviews

Most Helpful Customer Reviews

13 of 14 people found the following review helpful:

3.0 out of 5 stars works...but inadaquetly designed, November 28, 2010

By 

Lyle Josey (Florida) - See all my reviews
(REAL NAME)   

Amazon Verified Purchase

This review is from: Actron CP7828 Professional Compression Tester with Storage Pouch (Tools & Home Improvement)

Firstly, the product itself:
It functions, does what it says, isn't of bad quality overall, comes in a nice little case, has adapters which could be useful (I'll talk more on that in a sec) and comes with spare O-rings.

I like the fact that the gauge is housed in rubber, makes it seem less likely to be broken.
I like the length of the tube, but wish it could be longer.
I also wish the case was a tad nicer, but for the price, what can you expect?

NOW, after all he above. WHY did I give it 3 stars? I'll tell you why. The adapters are HORRIBLY DESIGNED. Maybe its plain bad luck on my part, maybe its plain good luck for most of the past reviewers of this product to not have had this problem or not have needed to use the adapters. EITHER WAY, BEWARE.

Here is what happened:

The FIRST TIME in using this product on a car (a '97 Camry, 5s-fe 4 cylinder engine), I put on the adapter for the car making sure to screw it on tight enough so as to where it would not come off easily. (I originally didn't need the adapter, the thread types are the same on the adapter and on the hose, I didn't know that at the time). Following which I took it out to the car, removed the spark plugs/wires and began testing one cylinder at a time.

Unbeknownst to me, the adapter had come off in the testing (in cylinder number 2), and because the thread types on the adapter and the hose are the same, I did not know it, the gauge/hose had continued to screw in as if it still had the adapter on it. So, I went to put the spark plugs back in, and because the adapter and the hose have the same threads, that means the spark plugs will FIT into the top of the adapter. So, cylinder number one went in fine, then came cylinder number two, the spark plug went in fine at first, then as the spark plug was being screwed in it felt unusual, but it wasn't much, I thought nothing of it. I backed it out once to make sure I didn't cross thread it. This was just the hand-tight pass, I put all the spark plugs in and went back to torque them down. Once I came upon cylinder number two, I began to torque it down, got to between 5 and 15 foot pounds and realized that it was binding, knew it wasn't normal and pulled it out.

To my horror, in my hand lay a spark plug with a ceramic insulator that had been crushed to pieces. With an unknown amount falling into the cylinder head/combustion chamber. As if that wasn't bad enough, I had an adapter that could not be removed, and was torqued between 5 and 15 foot pounds into the block of the engine. To make a VERY long explanation short, there very few ways of removing the adapter short of removing the head of the engine, I wasn't about to give up though. The adapter has a nut shaped head on it that could have a socket put around it, but the socket which fit the adapter would not fit down the spark plug tubes. I had few options left. I tried many things, easy outs (with great caution, I had no desire to get metal shavings into the cylinder), and rat tail files (forcing them into the adapter and attempting to unscrew it, it was too tight and the rat tail file too small to take the torque, at one point part of it snapped off).

I finally came to the conclusion that the best way to get out the adapter was to take the ruined spark plug and carefully JB Weld it into the the adapter. I did so.
Luck smiled upon me the following day and the adapter (and spark plug) came unscrewed as one with about 5 pounds of force. I vacuumed out the cylinder using a tube to get out any metal shavings/porcelain pieces that had fallen into the cylinder and replaced all spark plugs and wires. No binding with the plugs this time. Thank god.

The engine turned over and is still running great as of this review with around 10000 miles put on it since that incident.

Never again will I use an adapter with this kit without GREAT CAUTION. It is also why I am giving it three stars rather than the impulsive one or two. Overall the kit isn't bad, you just have to be careful. I recommend you use great caution when using the adapters in an engine where the spark plug tubes are long and/or thin.

BE CAREFUL with the adapters or you may end up in a similar situation. The only reason I ended where I did was negligence on my part, poorly designed adapters on there part (they shouldn't be threaded on, they should be attached some other way), and pure bad luck with the adapter, the hose, and my engine block all having the same thread.

oh and the engine checked out, compression was normal on all cylinders. The reason I put the story up with such great description is so that anyone who doubts my claim about the effectiveness of the adapters can read the story and understand for themselves what can happen. I do know that part of this was my fault, but it was also the design of the adapters that were at fault.

overall, I recommend the kit, with the above warning.

9 of 10 people found the following review helpful:

5.0 out of 5 stars Works exactly as described, April 6, 2007

By 

Michael Hogman (Canada) - See all my reviews
(REAL NAME)   

This review is from: Actron CP7828 Professional Compression Tester with Storage Pouch (Tools & Home Improvement)

Works exactly as described and seems so far to be very durable. Comes with attachments to do many types of engines

8 of 10 people found the following review helpful:

5.0 out of 5 stars ACTRON CP7828 COMPRESSION TESTER, April 8, 2008

By 

Ahmet GOKTAS "Ahmet GÖKTAS" (Ankara TURKEY) - See all my reviews
(REAL NAME)   

This review is from: Actron CP7828 Professional Compression Tester with Storage Pouch (Tools & Home Improvement)

I bought this tester for checking the compression of my vintage motorcycle, it worked very good.
It has many adapter pieces to fit different spark plug holes, additionally it comes with spare parts (different o-rings & small release valve)
I recommend this item for those who want to work on their engines
Ahmet Göktaº