You are here:

Triumph Repair/tr7 rpms and rattle

Advertisement


Question
New to tr7s so thanks for your help
1st.  Car seems to be completely wound out at4000 or so rpm  is that right?

2nd  I have a noise that sounds like a rattle on decelleration of the engine.  it happens if I am standing still or driving it comes from the engine and sounds like a metal rattle, but could be exhaust leak.  please respond by email as I have no idea how i found you on the web

Thanks
Bruce fahnestock
Dunedin FL  34698

Answer
Hi Bruce,

No, it is not normal to be wound out at 4000 RPM. That can me minor or major so some tests are necessary to pinpoint the problem.

As for a metallic rattle that too can me minor or major so it too needs to be attended to.

If that car came to me in a dealership I would have to run some tests as you now must do.

You will need a few tools besides standard hand tools but they are not expensive and will serve you well from now on. You need an hydraulic oil pressure gauge and a compression gauge. These are available at most any auto parts stores.

First is a compression test. Remove all four spark plugs and insert the compression gauge and Open the throttle wide open when you spin the starter motor so that the engine rotates at least 4 or 5 revolutions. You should see from 135 PSI to 170 PSI on all four cylinders and you don't want to see much difference between cylinders. Contact me again with the readings you get. Don't forget to OPEN the throttle on each test.

The oil pressure gauge will come as a kit with a long plastic hose and several fittings. You will have to locate the oil pressure warning light switch on the side of the block near the oil filter and remove the sending switch and note the size of the threads and match it up to one of the fittings in the kit you got from the parts store with a oil pressure gauge and install that fitting in the hole and fit the plastic hose and place the gauge where you can see it when you start the engine and let it idle and read the oil pressure. You should see from 25 PSI to 65 PSI (25 to 35 is normal with hot oil) Write down the readings and set the RPM at about 2000 RPM and read it again and write it down. You should see from 45 PSI to 65 PSI. Let me know the readings.

These two tests are 100% necessary BEFORE you start looking for the rattle or the short RPM range you have. Let me know.

Howard  

Triumph Repair

All Answers


Answers by Expert:


Ask Experts

Volunteer


Howard M. Fitzcharles III

Expertise

Triumph TR-4 up & Spitfire, and Engine theory

Experience

Dealership line mechanic on MG, Triumph, Jaguar for 15 years, Instructor in commercial mechanics school 2 yr. Product information manager for piston and valve manufacture, Instructor & hotline answer man for import car parts importer 15 yrs.

Organizations
Associate member SAE EAA member

Publications
Import Car magazine

Education/Credentials
ASE Master Auto with L-1 certification up to 2000

©2016 About.com. All rights reserved.